diff --git a/index.html b/index.html
index 9bc8673..45fde48 100644
--- a/index.html
+++ b/index.html
@@ -203,6 +203,12 @@
             font-size: 0.95em;
         }
 
+        .unit-indicator {
+            color: #88cc88;
+            font-weight: bold;
+            font-size: 0.85em;
+        }
+
         .input-group input {
             padding: 12px;
             background-color: #333333;
@@ -226,6 +232,7 @@
             align-items: center;
             padding: 10px 0;
             border-bottom: 1px solid #3a3a3a;
+            position: relative;
         }
 
         .result-item:last-child {
@@ -236,6 +243,13 @@
             color: #cccccc;
             font-weight: normal;
             flex: 1;
+            cursor: help;
+        }
+
+        .result-value-container {
+            display: flex;
+            align-items: center;
+            gap: 8px;
         }
 
         .result-value {
@@ -244,6 +258,44 @@
             text-align: right;
             font-weight: bold;
             min-width: 120px;
+            cursor: help;
+        }
+
+        .copy-btn {
+            background: none;
+            border: none;
+            color: #888888;
+            cursor: pointer;
+            padding: 4px;
+            border-radius: 3px;
+            transition: all 0.2s;
+            font-size: 14px;
+        }
+
+        .copy-btn:hover {
+            color: #ffffff;
+            background-color: #404040;
+        }
+
+        .copy-btn:active {
+            color: #88cc88;
+        }
+
+        /* Tooltip */
+        .tooltip {
+            position: absolute;
+            background-color: #1a1a1a;
+            color: #ffffff;
+            padding: 8px 12px;
+            border-radius: 4px;
+            font-size: 0.85em;
+            border: 1px solid #555555;
+            z-index: 1000;
+            max-width: 400px;
+            word-wrap: break-word;
+            box-shadow: 0 4px 8px rgba(0,0,0,0.3);
+            font-family: 'Consolas', monospace;
+            line-height: 1.4;
         }
 
         @media (max-width: 600px) {
@@ -378,11 +430,11 @@
                     <h2>Konstanten</h2>
                     <div class="input-grid">
                         <div class="input-group">
-                            <label for="baseOffset1216">Base Offset (Partition Start):</label>
+                            <label for="baseOffset1216">Base Offset <span class="unit-indicator">(Bytes)</span>:</label>
                             <input type="text" id="baseOffset1216" value="0x0" placeholder="0x0">
                         </div>
                         <div class="input-group">
-                            <label for="sectorSize1216">Größe eines Sektors (Bytes):</label>
+                            <label for="sectorSize1216">Größe eines Sektors <span class="unit-indicator">(Bytes)</span>:</label>
                             <input type="text" id="sectorSize1216" value="0x200" placeholder="0x200">
                         </div>
                     </div>
@@ -392,31 +444,31 @@
                     <h2>Eingabeparameter</h2>
                     <div class="input-grid">
                         <div class="input-group">
-                            <label for="reservedSectors1216">Anzahl reservierter Sektoren:</label>
+                            <label for="reservedSectors1216">Anzahl reservierter Sektoren <span class="unit-indicator">(Sektoren)</span>:</label>
                             <input type="text" id="reservedSectors1216" placeholder="0x1">
                         </div>
                         <div class="input-group">
-                            <label for="numFATs1216">Anzahl FATs:</label>
+                            <label for="numFATs1216">Anzahl FATs <span class="unit-indicator">(Anzahl)</span>:</label>
                             <input type="text" id="numFATs1216" placeholder="0x2">
                         </div>
                         <div class="input-group">
-                            <label for="fatSizeBytes1216">Größe einer FAT (Bytes):</label>
+                            <label for="fatSizeBytes1216">Größe einer FAT <span class="unit-indicator">(Bytes)</span>:</label>
                             <input type="text" id="fatSizeBytes1216" placeholder="0x1000">
                         </div>
                         <div class="input-group">
-                            <label for="maxRootEntries1216">Anzahl max. Wurzelverzeichnis-Einträge:</label>
+                            <label for="maxRootEntries1216">Max. Wurzelverzeichnis-Einträge <span class="unit-indicator">(Anzahl)</span>:</label>
                             <input type="text" id="maxRootEntries1216" placeholder="0x200">
                         </div>
                         <div class="input-group">
-                            <label for="partitionSize1216">Größe Partition (Bytes):</label>
-                            <input type="text" id="partitionSize1216" placeholder="0x100000">
+                            <label for="partitionSizeInSectors1216">Größe Partition <span class="unit-indicator">(Sektoren)</span>:</label>
+                            <input type="text" id="partitionSizeInSectors1216" placeholder="0x4015">
                         </div>
                         <div class="input-group">
-                            <label for="clusterSizeSectors1216">Größe eines Clusters (Sektoren):</label>
+                            <label for="clusterSizeSectors1216">Größe eines Clusters <span class="unit-indicator">(Sektoren)</span>:</label>
                             <input type="text" id="clusterSizeSectors1216" placeholder="0x1">
                         </div>
                         <div class="input-group">
-                            <label for="clusterNumber1216">Cluster Nummer (für Position):</label>
+                            <label for="clusterNumber1216">Cluster Nummer für Position <span class="unit-indicator">(Nummer)</span>:</label>
                             <input type="text" id="clusterNumber1216" placeholder="0x2">
                         </div>
                     </div>
@@ -426,40 +478,67 @@
                     <h2>Berechnete Werte</h2>
                     <div id="results1216">
                         <div class="result-item">
-                            <span class="result-label">Beginn FAT-Bereich:</span>
-                            <span class="result-value" id="fatStart1216">-</span>
+                            <span class="result-label" data-formula="reservedSectors × sectorSize + baseOffset">Beginn FAT-Bereich:</span>
+                            <div class="result-value-container">
+                                <span class="result-value" id="fatStart1216" data-result-formula="">-</span>
+                                <button class="copy-btn" onclick="copyToClipboard('fatStart1216')" title="Copy to clipboard">📋</button>
+                            </div>
                         </div>
                         <div class="result-item">
-                            <span class="result-label">Größe FAT-Bereich:</span>
-                            <span class="result-value" id="fatSize1216">-</span>
+                            <span class="result-label" data-formula="numFATs × fatSizeBytes">Größe FAT-Bereich:</span>
+                            <div class="result-value-container">
+                                <span class="result-value" id="fatSize1216" data-result-formula="">-</span>
+                                <button class="copy-btn" onclick="copyToClipboard('fatSize1216')" title="Copy to clipboard">📋</button>
+                            </div>
                         </div>
                         <div class="result-item">
-                            <span class="result-label">Ende FAT-Bereich:</span>
-                            <span class="result-value" id="fatEnd1216">-</span>
+                            <span class="result-label" data-formula="fatStart + fatSize">Ende FAT-Bereich:</span>
+                            <div class="result-value-container">
+                                <span class="result-value" id="fatEnd1216" data-result-formula="">-</span>
+                                <button class="copy-btn" onclick="copyToClipboard('fatEnd1216')" title="Copy to clipboard">📋</button>
+                            </div>
                         </div>
                         <div class="result-item">
-                            <span class="result-label">Größe Wurzelverzeichnis:</span>
-                            <span class="result-value" id="rootDirSize1216">-</span>
+                            <span class="result-label" data-formula="maxRootEntries × 0x20">Größe Wurzelverzeichnis:</span>
+                            <div class="result-value-container">
+                                <span class="result-value" id="rootDirSize1216" data-result-formula="">-</span>
+                                <button class="copy-btn" onclick="copyToClipboard('rootDirSize1216')" title="Copy to clipboard">📋</button>
+                            </div>
                         </div>
                         <div class="result-item">
-                            <span class="result-label">Beginn Daten-Bereich:</span>
-                            <span class="result-value" id="dataStart1216">-</span>
+                            <span class="result-label" data-formula="fatEnd + rootDirSize">Beginn Daten-Bereich:</span>
+                            <div class="result-value-container">
+                                <span class="result-value" id="dataStart1216" data-result-formula="">-</span>
+                                <button class="copy-btn" onclick="copyToClipboard('dataStart1216')" title="Copy to clipboard">📋</button>
+                            </div>
                         </div>
                         <div class="result-item">
-                            <span class="result-label">Größe Daten-Bereich:</span>
-                            <span class="result-value" id="dataSize1216">-</span>
+                            <span class="result-label" data-formula="(partitionSizeInSectors × sectorSize) - (dataStart - baseOffset)">Größe Daten-Bereich:</span>
+                            <div class="result-value-container">
+                                <span class="result-value" id="dataSize1216" data-result-formula="">-</span>
+                                <button class="copy-btn" onclick="copyToClipboard('dataSize1216')" title="Copy to clipboard">📋</button>
+                            </div>
                         </div>
                         <div class="result-item">
-                            <span class="result-label">Größe eines Clusters:</span>
-                            <span class="result-value" id="clusterSize1216">-</span>
+                            <span class="result-label" data-formula="sectorSize × clusterSizeSectors">Größe eines Clusters:</span>
+                            <div class="result-value-container">
+                                <span class="result-value" id="clusterSize1216" data-result-formula="">-</span>
+                                <button class="copy-btn" onclick="copyToClipboard('clusterSize1216')" title="Copy to clipboard">📋</button>
+                            </div>
                         </div>
                         <div class="result-item">
-                            <span class="result-label">Anzahl Cluster:</span>
-                            <span class="result-value" id="numClusters1216">-</span>
+                            <span class="result-label" data-formula="dataSize ÷ clusterSize">Anzahl Cluster:</span>
+                            <div class="result-value-container">
+                                <span class="result-value" id="numClusters1216" data-result-formula="">-</span>
+                                <button class="copy-btn" onclick="copyToClipboard('numClusters1216')" title="Copy to clipboard">📋</button>
+                            </div>
                         </div>
                         <div class="result-item">
-                            <span class="result-label">Beginn Cluster:</span>
-                            <span class="result-value" id="clusterStart1216">-</span>
+                            <span class="result-label" data-formula="dataStart + (clusterNumber - 0x2) × clusterSize">Beginn Cluster:</span>
+                            <div class="result-value-container">
+                                <span class="result-value" id="clusterStart1216" data-result-formula="">-</span>
+                                <button class="copy-btn" onclick="copyToClipboard('clusterStart1216')" title="Copy to clipboard">📋</button>
+                            </div>
                         </div>
                     </div>
                 </div>
@@ -472,7 +551,7 @@
                         <div class="formula"><span class="calculated">Ende FAT-Bereich</span> = Beginn FAT-Bereich + Größe FAT-Bereich</div>
                         <div class="formula"><span class="calculated">Größe Wurzelverzeichnis</span> = Anzahl max. Wurzelverzeichnis-Einträge × 0x20</div>
                         <div class="formula"><span class="calculated">Beginn Daten-Bereich</span> = Ende FAT-Bereich + Größe Wurzelverzeichnis</div>
-                        <div class="formula"><span class="calculated">Größe Daten-Bereich</span> = Größe Partition - (Beginn Daten-Bereich - Base Offset)</div>
+                        <div class="formula"><span class="calculated">Größe Daten-Bereich</span> = (Größe Partition in Sektoren × Größe eines Sektors) - (Beginn Daten-Bereich - Base Offset)</div>
                         <div class="formula"><span class="calculated">Größe eines Clusters</span> = Größe eines Sektors × Größe eines Clusters in Sektoren</div>
                         <div class="formula"><span class="calculated">Anzahl Cluster</span> = Größe Daten-Bereich ÷ Größe eines Clusters</div>
                         <div class="formula"><span class="calculated">Beginn Cluster</span> = Beginn Daten-Bereich + (Cluster - 0x2) × Größe eines Clusters</div>
@@ -486,11 +565,11 @@
                     <h2>Konstanten</h2>
                     <div class="input-grid">
                         <div class="input-group">
-                            <label for="baseOffset32">Base Offset (Partition Start):</label>
+                            <label for="baseOffset32">Base Offset <span class="unit-indicator">(Bytes)</span>:</label>
                             <input type="text" id="baseOffset32" value="0x0" placeholder="0x0">
                         </div>
                         <div class="input-group">
-                            <label for="sectorSize32">Größe eines Sektors (Bytes):</label>
+                            <label for="sectorSize32">Größe eines Sektors <span class="unit-indicator">(Bytes)</span>:</label>
                             <input type="text" id="sectorSize32" value="0x200" placeholder="0x200">
                         </div>
                     </div>
@@ -500,31 +579,31 @@
                     <h2>Eingabeparameter</h2>
                     <div class="input-grid">
                         <div class="input-group">
-                            <label for="reservedSectors32">Anzahl reservierter Sektoren:</label>
+                            <label for="reservedSectors32">Anzahl reservierter Sektoren <span class="unit-indicator">(Sektoren)</span>:</label>
                             <input type="text" id="reservedSectors32" placeholder="0x20">
                         </div>
                         <div class="input-group">
-                            <label for="numFATs32">Anzahl FATs:</label>
+                            <label for="numFATs32">Anzahl FATs <span class="unit-indicator">(Anzahl)</span>:</label>
                             <input type="text" id="numFATs32" placeholder="0x2">
                         </div>
                         <div class="input-group">
-                            <label for="fatSizeBytes32">Größe einer FAT (Bytes):</label>
+                            <label for="fatSizeBytes32">Größe einer FAT <span class="unit-indicator">(Bytes)</span>:</label>
                             <input type="text" id="fatSizeBytes32" placeholder="0x10000">
                         </div>
                         <div class="input-group">
-                            <label for="rootDirCluster32">Root Directory Cluster:</label>
+                            <label for="rootDirCluster32">Root Directory Cluster <span class="unit-indicator">(Nummer)</span>:</label>
                             <input type="text" id="rootDirCluster32" placeholder="0x2">
                         </div>
                         <div class="input-group">
-                            <label for="partitionSize32">Größe Partition (Bytes):</label>
-                            <input type="text" id="partitionSize32" placeholder="0x10000000">
+                            <label for="partitionSizeInSectors32">Größe Partition <span class="unit-indicator">(Sektoren)</span>:</label>
+                            <input type="text" id="partitionSizeInSectors32" placeholder="0x20000">
                         </div>
                         <div class="input-group">
-                            <label for="clusterSizeSectors32">Größe eines Clusters (Sektoren):</label>
+                            <label for="clusterSizeSectors32">Größe eines Clusters <span class="unit-indicator">(Sektoren)</span>:</label>
                             <input type="text" id="clusterSizeSectors32" placeholder="0x8">
                         </div>
                         <div class="input-group">
-                            <label for="clusterNumber32">Cluster Nummer (für Position):</label>
+                            <label for="clusterNumber32">Cluster Nummer für Position <span class="unit-indicator">(Nummer)</span>:</label>
                             <input type="text" id="clusterNumber32" placeholder="0x2">
                         </div>
                     </div>
@@ -534,40 +613,67 @@
                     <h2>Berechnete Werte</h2>
                     <div id="results32">
                         <div class="result-item">
-                            <span class="result-label">Beginn FAT-Bereich:</span>
-                            <span class="result-value" id="fatStart32">-</span>
+                            <span class="result-label" data-formula="reservedSectors × sectorSize + baseOffset">Beginn FAT-Bereich:</span>
+                            <div class="result-value-container">
+                                <span class="result-value" id="fatStart32" data-result-formula="">-</span>
+                                <button class="copy-btn" onclick="copyToClipboard('fatStart32')" title="Copy to clipboard">📋</button>
+                            </div>
                         </div>
                         <div class="result-item">
-                            <span class="result-label">Größe FAT-Bereich:</span>
-                            <span class="result-value" id="fatSize32">-</span>
+                            <span class="result-label" data-formula="numFATs × fatSizeBytes">Größe FAT-Bereich:</span>
+                            <div class="result-value-container">
+                                <span class="result-value" id="fatSize32" data-result-formula="">-</span>
+                                <button class="copy-btn" onclick="copyToClipboard('fatSize32')" title="Copy to clipboard">📋</button>
+                            </div>
                         </div>
                         <div class="result-item">
-                            <span class="result-label">Ende FAT-Bereich:</span>
-                            <span class="result-value" id="fatEnd32">-</span>
+                            <span class="result-label" data-formula="fatStart + fatSize">Ende FAT-Bereich:</span>
+                            <div class="result-value-container">
+                                <span class="result-value" id="fatEnd32" data-result-formula="">-</span>
+                                <button class="copy-btn" onclick="copyToClipboard('fatEnd32')" title="Copy to clipboard">📋</button>
+                            </div>
                         </div>
                         <div class="result-item">
-                            <span class="result-label">Beginn Daten-Bereich:</span>
-                            <span class="result-value" id="dataStart32">-</span>
+                            <span class="result-label" data-formula="fatEnd">Beginn Daten-Bereich:</span>
+                            <div class="result-value-container">
+                                <span class="result-value" id="dataStart32" data-result-formula="">-</span>
+                                <button class="copy-btn" onclick="copyToClipboard('dataStart32')" title="Copy to clipboard">📋</button>
+                            </div>
                         </div>
                         <div class="result-item">
-                            <span class="result-label">Größe Daten-Bereich:</span>
-                            <span class="result-value" id="dataSize32">-</span>
+                            <span class="result-label" data-formula="(partitionSizeInSectors × sectorSize) - (dataStart - baseOffset)">Größe Daten-Bereich:</span>
+                            <div class="result-value-container">
+                                <span class="result-value" id="dataSize32" data-result-formula="">-</span>
+                                <button class="copy-btn" onclick="copyToClipboard('dataSize32')" title="Copy to clipboard">📋</button>
+                            </div>
                         </div>
                         <div class="result-item">
-                            <span class="result-label">Größe eines Clusters:</span>
-                            <span class="result-value" id="clusterSize32">-</span>
+                            <span class="result-label" data-formula="sectorSize × clusterSizeSectors">Größe eines Clusters:</span>
+                            <div class="result-value-container">
+                                <span class="result-value" id="clusterSize32" data-result-formula="">-</span>
+                                <button class="copy-btn" onclick="copyToClipboard('clusterSize32')" title="Copy to clipboard">📋</button>
+                            </div>
                         </div>
                         <div class="result-item">
-                            <span class="result-label">Anzahl Cluster:</span>
-                            <span class="result-value" id="numClusters32">-</span>
+                            <span class="result-label" data-formula="dataSize ÷ clusterSize">Anzahl Cluster:</span>
+                            <div class="result-value-container">
+                                <span class="result-value" id="numClusters32" data-result-formula="">-</span>
+                                <button class="copy-btn" onclick="copyToClipboard('numClusters32')" title="Copy to clipboard">📋</button>
+                            </div>
                         </div>
                         <div class="result-item">
-                            <span class="result-label">Beginn Cluster:</span>
-                            <span class="result-value" id="clusterStart32">-</span>
+                            <span class="result-label" data-formula="dataStart + (clusterNumber - 0x2) × clusterSize">Beginn Cluster:</span>
+                            <div class="result-value-container">
+                                <span class="result-value" id="clusterStart32" data-result-formula="">-</span>
+                                <button class="copy-btn" onclick="copyToClipboard('clusterStart32')" title="Copy to clipboard">📋</button>
+                            </div>
                         </div>
                         <div class="result-item">
-                            <span class="result-label">Root Directory Position:</span>
-                            <span class="result-value" id="rootDirPos32">-</span>
+                            <span class="result-label" data-formula="dataStart + (rootDirCluster - 0x2) × clusterSize">Root Directory Position:</span>
+                            <div class="result-value-container">
+                                <span class="result-value" id="rootDirPos32" data-result-formula="">-</span>
+                                <button class="copy-btn" onclick="copyToClipboard('rootDirPos32')" title="Copy to clipboard">📋</button>
+                            </div>
                         </div>
                     </div>
                 </div>
@@ -579,7 +685,7 @@
                         <div class="formula"><span class="calculated">Größe FAT-Bereich</span> = Anzahl FATs × Größe einer FAT</div>
                         <div class="formula"><span class="calculated">Ende FAT-Bereich</span> = Beginn FAT-Bereich + Größe FAT-Bereich</div>
                         <div class="formula"><span class="calculated">Beginn Daten-Bereich</span> = Ende FAT-Bereich (kein festes Root Directory)</div>
-                        <div class="formula"><span class="calculated">Größe Daten-Bereich</span> = Größe Partition - (Beginn Daten-Bereich - Base Offset)</div>
+                        <div class="formula"><span class="calculated">Größe Daten-Bereich</span> = (Größe Partition in Sektoren × Größe eines Sektors) - (Beginn Daten-Bereich - Base Offset)</div>
                         <div class="formula"><span class="calculated">Größe eines Clusters</span> = Größe eines Sektors × Größe eines Clusters in Sektoren</div>
                         <div class="formula"><span class="calculated">Anzahl Cluster</span> = Größe Daten-Bereich ÷ Größe eines Clusters</div>
                         <div class="formula"><span class="calculated">Beginn Cluster</span> = Beginn Daten-Bereich + (Cluster - 0x2) × Größe eines Clusters</div>
@@ -595,7 +701,7 @@
             <div class="footer-section">
                 <h3>About</h3>
                 <p>Filesystem calculator for educational and forensic purposes.</p>
-                <p>Version 0.1.0</p>
+                <p>Version 0.2.0</p>
             </div>
             <div class="footer-section">
                 <h3>Support</h3>
@@ -619,10 +725,55 @@
     </footer>
 
     <script>
+        // Global tooltip element
+        let tooltip = null;
+
+        // Create tooltip element
+        function createTooltip() {
+            if (!tooltip) {
+                tooltip = document.createElement('div');
+                tooltip.className = 'tooltip';
+                tooltip.style.display = 'none';
+                document.body.appendChild(tooltip);
+            }
+        }
+
+        // Show tooltip
+        function showTooltip(element, text) {
+            createTooltip();
+            tooltip.innerHTML = text;
+            tooltip.style.display = 'block';
+            
+            const rect = element.getBoundingClientRect();
+            const tooltipRect = tooltip.getBoundingClientRect();
+            
+            let left = rect.left + (rect.width / 2) - (tooltipRect.width / 2);
+            let top = rect.top - tooltipRect.height - 8;
+            
+            // Keep tooltip within viewport
+            if (left < 10) left = 10;
+            if (left + tooltipRect.width > window.innerWidth - 10) {
+                left = window.innerWidth - tooltipRect.width - 10;
+            }
+            if (top < 10) {
+                top = rect.bottom + 8;
+            }
+            
+            tooltip.style.left = left + 'px';
+            tooltip.style.top = top + 'px';
+        }
+
+        // Hide tooltip
+        function hideTooltip() {
+            if (tooltip) {
+                tooltip.style.display = 'none';
+            }
+        }
+
         // Filesystem calculation implementations
         const filesystems = {
             fat1216: {
-                requiredFields: ['reservedSectors1216', 'numFATs1216', 'fatSizeBytes1216', 'maxRootEntries1216', 'partitionSize1216', 'clusterSizeSectors1216'],
+                requiredFields: ['reservedSectors1216', 'numFATs1216', 'fatSizeBytes1216', 'maxRootEntries1216', 'partitionSizeInSectors1216', 'clusterSizeSectors1216'],
                 calculate: function() {
                     const baseOffset = parseHex(document.getElementById('baseOffset1216').value);
                     const sectorSize = parseHex(document.getElementById('sectorSize1216').value);
@@ -630,7 +781,7 @@
                     const numFATs = parseHex(document.getElementById('numFATs1216').value);
                     const fatSizeBytes = parseHex(document.getElementById('fatSizeBytes1216').value);
                     const maxRootEntries = parseHex(document.getElementById('maxRootEntries1216').value);
-                    const partitionSize = parseHex(document.getElementById('partitionSize1216').value);
+                    const partitionSizeInSectors = parseHex(document.getElementById('partitionSizeInSectors1216').value);
                     const clusterSizeSectors = parseHex(document.getElementById('clusterSizeSectors1216').value);
                     const clusterNumber = parseHex(document.getElementById('clusterNumber1216').value);
 
@@ -639,19 +790,32 @@
                     const fatEnd = fatStart + fatSize;
                     const rootDirSize = maxRootEntries * 0x20;
                     const dataStart = fatEnd + rootDirSize;
-                    const dataSize = partitionSize - (dataStart - baseOffset);
+                    const dataSize = partitionSizeInSectors * sectorSize - (dataStart - baseOffset);
                     const clusterSize = sectorSize * clusterSizeSectors;
                     const numClusters = clusterSize > 0 ? Math.floor(dataSize / clusterSize) : 0;
                     const clusterStart = dataStart + (clusterNumber - 0x2) * clusterSize;
 
+                    // Store calculation formulas with actual values
+                    const calculations = {
+                        fatStart: `${reservedSectors.toString(16)} × ${sectorSize.toString(16)} + ${baseOffset.toString(16)} = ${fatStart.toString(16)}`,
+                        fatSize: `${numFATs.toString(16)} × ${fatSizeBytes.toString(16)} = ${fatSize.toString(16)}`,
+                        fatEnd: `${fatStart.toString(16)} + ${fatSize.toString(16)} = ${fatEnd.toString(16)}`,
+                        rootDirSize: `${maxRootEntries.toString(16)} × 0x20 = ${rootDirSize.toString(16)}`,
+                        dataStart: `${fatEnd.toString(16)} + ${rootDirSize.toString(16)} = ${dataStart.toString(16)}`,
+                        dataSize: `(${partitionSizeInSectors.toString(16)} × ${sectorSize.toString(16)}) - (${dataStart.toString(16)} - ${baseOffset.toString(16)}) = ${dataSize.toString(16)}`,
+                        clusterSize: `${sectorSize.toString(16)} × ${clusterSizeSectors.toString(16)} = ${clusterSize.toString(16)}`,
+                        numClusters: `${dataSize.toString(16)} ÷ ${clusterSize.toString(16)} = ${numClusters.toString(16)}`,
+                        clusterStart: `${dataStart.toString(16)} + (${clusterNumber.toString(16)} - 0x2) × ${clusterSize.toString(16)} = ${clusterStart.toString(16)}`
+                    };
+
                     return {
                         fatStart, fatSize, fatEnd, rootDirSize, dataStart, dataSize, 
-                        clusterSize, numClusters, clusterStart
+                        clusterSize, numClusters, clusterStart, calculations
                     };
                 }
             },
             fat32: {
-                requiredFields: ['reservedSectors32', 'numFATs32', 'fatSizeBytes32', 'rootDirCluster32', 'partitionSize32', 'clusterSizeSectors32'],
+                requiredFields: ['reservedSectors32', 'numFATs32', 'fatSizeBytes32', 'rootDirCluster32', 'partitionSizeInSectors32', 'clusterSizeSectors32'],
                 calculate: function() {
                     const baseOffset = parseHex(document.getElementById('baseOffset32').value);
                     const sectorSize = parseHex(document.getElementById('sectorSize32').value);
@@ -659,23 +823,35 @@
                     const numFATs = parseHex(document.getElementById('numFATs32').value);
                     const fatSizeBytes = parseHex(document.getElementById('fatSizeBytes32').value);
                     const rootDirCluster = parseHex(document.getElementById('rootDirCluster32').value);
-                    const partitionSize = parseHex(document.getElementById('partitionSize32').value);
+                    const partitionSizeInSectors = parseHex(document.getElementById('partitionSizeInSectors32').value);
                     const clusterSizeSectors = parseHex(document.getElementById('clusterSizeSectors32').value);
                     const clusterNumber = parseHex(document.getElementById('clusterNumber32').value);
 
                     const fatStart = reservedSectors * sectorSize + baseOffset;
                     const fatSize = numFATs * fatSizeBytes;
                     const fatEnd = fatStart + fatSize;
-                    const dataStart = fatEnd; // No fixed root directory in FAT32
-                    const dataSize = partitionSize - (dataStart - baseOffset);
+                    const dataStart = fatEnd;
+                    const dataSize = partitionSizeInSectors * sectorSize - (dataStart - baseOffset);
                     const clusterSize = sectorSize * clusterSizeSectors;
                     const numClusters = clusterSize > 0 ? Math.floor(dataSize / clusterSize) : 0;
                     const clusterStart = dataStart + (clusterNumber - 0x2) * clusterSize;
                     const rootDirPos = dataStart + (rootDirCluster - 0x2) * clusterSize;
 
+                    const calculations = {
+                        fatStart: `${reservedSectors.toString(16)} × ${sectorSize.toString(16)} + ${baseOffset.toString(16)} = ${fatStart.toString(16)}`,
+                        fatSize: `${numFATs.toString(16)} × ${fatSizeBytes.toString(16)} = ${fatSize.toString(16)}`,
+                        fatEnd: `${fatStart.toString(16)} + ${fatSize.toString(16)} = ${fatEnd.toString(16)}`,
+                        dataStart: `${fatEnd.toString(16)}`,
+                        dataSize: `(${partitionSizeInSectors.toString(16)} × ${sectorSize.toString(16)}) - (${dataStart.toString(16)} - ${baseOffset.toString(16)}) = ${dataSize.toString(16)}`,
+                        clusterSize: `${sectorSize.toString(16)} × ${clusterSizeSectors.toString(16)} = ${clusterSize.toString(16)}`,
+                        numClusters: `${dataSize.toString(16)} ÷ ${clusterSize.toString(16)} = ${numClusters.toString(16)}`,
+                        clusterStart: `${dataStart.toString(16)} + (${clusterNumber.toString(16)} - 0x2) × ${clusterSize.toString(16)} = ${clusterStart.toString(16)}`,
+                        rootDirPos: `${dataStart.toString(16)} + (${rootDirCluster.toString(16)} - 0x2) × ${clusterSize.toString(16)} = ${rootDirPos.toString(16)}`
+                    };
+
                     return {
                         fatStart, fatSize, fatEnd, dataStart, dataSize, 
-                        clusterSize, numClusters, clusterStart, rootDirPos
+                        clusterSize, numClusters, clusterStart, rootDirPos, calculations
                     };
                 }
             }
@@ -698,21 +874,38 @@
             return '0x' + value.toString(16).toUpperCase();
         }
 
+        function copyToClipboard(elementId) {
+            const element = document.getElementById(elementId);
+            const text = element.textContent.trim();
+            
+            if (text === '-' || text.includes('Fehler')) {
+                return;
+            }
+            
+            navigator.clipboard.writeText(text).then(() => {
+                const btn = element.parentElement.querySelector('.copy-btn');
+                const originalText = btn.textContent;
+                btn.textContent = '✓';
+                btn.style.color = '#88cc88';
+                setTimeout(() => {
+                    btn.textContent = originalText;
+                    btn.style.color = '';
+                }, 1000);
+            }).catch(err => {
+                console.error('Failed to copy to clipboard:', err);
+            });
+        }
+
         function switchTab(tabId) {
-            // Hide all tab contents
             document.querySelectorAll('.tab-content').forEach(content => {
                 content.classList.remove('active');
             });
             
-            // Remove active class from all tabs
             document.querySelectorAll('.tab').forEach(tab => {
                 tab.classList.remove('active');
             });
             
-            // Show selected tab content
             document.getElementById(tabId).classList.add('active');
-            
-            // Add active class to clicked tab
             event.target.classList.add('active');
         }
 
@@ -726,27 +919,42 @@
 
                 const results = fs.calculate();
                 
-                // Update results based on filesystem type
                 if (fsType === 'fat1216') {
-                    document.getElementById('fatStart1216').innerHTML = formatHex(results.fatStart);
-                    document.getElementById('fatSize1216').innerHTML = formatHex(results.fatSize);
-                    document.getElementById('fatEnd1216').innerHTML = formatHex(results.fatEnd);
-                    document.getElementById('rootDirSize1216').innerHTML = formatHex(results.rootDirSize);
-                    document.getElementById('dataStart1216').innerHTML = formatHex(results.dataStart);
-                    document.getElementById('dataSize1216').innerHTML = formatHex(results.dataSize);
-                    document.getElementById('clusterSize1216').innerHTML = formatHex(results.clusterSize);
-                    document.getElementById('numClusters1216').innerHTML = formatHex(results.numClusters);
-                    document.getElementById('clusterStart1216').innerHTML = formatHex(results.clusterStart);
+                    const mapping = {
+                        'fatStart1216': ['fatStart', 'fatStart'],
+                        'fatSize1216': ['fatSize', 'fatSize'],
+                        'fatEnd1216': ['fatEnd', 'fatEnd'],
+                        'rootDirSize1216': ['rootDirSize', 'rootDirSize'],
+                        'dataStart1216': ['dataStart', 'dataStart'],
+                        'dataSize1216': ['dataSize', 'dataSize'],
+                        'clusterSize1216': ['clusterSize', 'clusterSize'],
+                        'numClusters1216': ['numClusters', 'numClusters'],
+                        'clusterStart1216': ['clusterStart', 'clusterStart']
+                    };
+                    
+                    Object.entries(mapping).forEach(([elementId, [resultKey, calcKey]]) => {
+                        const element = document.getElementById(elementId);
+                        element.innerHTML = formatHex(results[resultKey]);
+                        element.setAttribute('data-result-formula', results.calculations[calcKey]);
+                    });
                 } else if (fsType === 'fat32') {
-                    document.getElementById('fatStart32').innerHTML = formatHex(results.fatStart);
-                    document.getElementById('fatSize32').innerHTML = formatHex(results.fatSize);
-                    document.getElementById('fatEnd32').innerHTML = formatHex(results.fatEnd);
-                    document.getElementById('dataStart32').innerHTML = formatHex(results.dataStart);
-                    document.getElementById('dataSize32').innerHTML = formatHex(results.dataSize);
-                    document.getElementById('clusterSize32').innerHTML = formatHex(results.clusterSize);
-                    document.getElementById('numClusters32').innerHTML = formatHex(results.numClusters);
-                    document.getElementById('clusterStart32').innerHTML = formatHex(results.clusterStart);
-                    document.getElementById('rootDirPos32').innerHTML = formatHex(results.rootDirPos);
+                    const mapping = {
+                        'fatStart32': ['fatStart', 'fatStart'],
+                        'fatSize32': ['fatSize', 'fatSize'],
+                        'fatEnd32': ['fatEnd', 'fatEnd'],
+                        'dataStart32': ['dataStart', 'dataStart'],
+                        'dataSize32': ['dataSize', 'dataSize'],
+                        'clusterSize32': ['clusterSize', 'clusterSize'],
+                        'numClusters32': ['numClusters', 'numClusters'],
+                        'clusterStart32': ['clusterStart', 'clusterStart'],
+                        'rootDirPos32': ['rootDirPos', 'rootDirPos']
+                    };
+                    
+                    Object.entries(mapping).forEach(([elementId, [resultKey, calcKey]]) => {
+                        const element = document.getElementById(elementId);
+                        element.innerHTML = formatHex(results[resultKey]);
+                        element.setAttribute('data-result-formula', results.calculations[calcKey]);
+                    });
                 }
 
             } catch (error) {
@@ -759,32 +967,34 @@
             const fs = filesystems[fsType];
             if (!fs) return;
 
-            // Clear input fields
             fs.requiredFields.forEach(fieldId => {
                 const element = document.getElementById(fieldId);
                 if (element) element.value = '';
             });
 
-            // Clear cluster number field
             const clusterField = document.getElementById(`clusterNumber${fsType === 'fat1216' ? '1216' : '32'}`);
             if (clusterField) clusterField.value = '';
 
-            // Reset results
             if (fsType === 'fat1216') {
                 const resultElements = ['fatStart1216', 'fatSize1216', 'fatEnd1216', 'rootDirSize1216', 'dataStart1216', 'dataSize1216', 'clusterSize1216', 'numClusters1216', 'clusterStart1216'];
                 resultElements.forEach(id => {
-                    document.getElementById(id).innerHTML = '-';
+                    const element = document.getElementById(id);
+                    element.innerHTML = '-';
+                    element.setAttribute('data-result-formula', '');
                 });
             } else if (fsType === 'fat32') {
                 const resultElements = ['fatStart32', 'fatSize32', 'fatEnd32', 'dataStart32', 'dataSize32', 'clusterSize32', 'numClusters32', 'clusterStart32', 'rootDirPos32'];
                 resultElements.forEach(id => {
-                    document.getElementById(id).innerHTML = '-';
+                    const element = document.getElementById(id);
+                    element.innerHTML = '-';
+                    element.setAttribute('data-result-formula', '');
                 });
             }
         }
 
-        // Add event listeners for real-time calculation
+        // Add event listeners
         document.addEventListener('DOMContentLoaded', function() {
+            // Real-time calculation
             Object.keys(filesystems).forEach(fsType => {
                 const fs = filesystems[fsType];
                 fs.requiredFields.forEach(fieldId => {
@@ -801,9 +1011,31 @@
                     }
                 });
             });
+
+            // Tooltip event listeners
+            document.addEventListener('mouseover', function(e) {
+                if (e.target.classList.contains('result-label')) {
+                    const formula = e.target.getAttribute('data-formula');
+                    if (formula) {
+                        showTooltip(e.target, `Formula: ${formula}`);
+                    }
+                } else if (e.target.classList.contains('result-value')) {
+                    const formula = e.target.getAttribute('data-result-formula');
+                    if (formula && formula !== '') {
+                        showTooltip(e.target, `Calculation: ${formula}`);
+                    }
+                }
+            });
+
+            document.addEventListener('mouseout', function(e) {
+                if (e.target.classList.contains('result-label') || e.target.classList.contains('result-value')) {
+                    hideTooltip();
+                }
+            });
+
+            // Hide tooltip when scrolling
+            document.addEventListener('scroll', hideTooltip);
         });
     </script>
 </body>
-</html>
-
-87.123.43.152
\ No newline at end of file
+</html>
\ No newline at end of file