Electrical Conduit Size Calculator Link May 2026

function computeTotalArea() let total = 0; for (let w of wires) const areaObj = wireAreas[w.size]; if (areaObj && areaObj[w.insulation]) total += areaObj[w.insulation]; else if (areaObj && areaObj["THHN"]) total += areaObj["THHN"]; else total += 0.0133; // fallback return total;

// initialization function init() wires.push( size: "12", insulation: "THHN" ); wires.push( size: "12", insulation: "THHN" ); renderWireInputs(); document.getElementById('addWireBtn').addEventListener('click', addWire); document.getElementById('calculateBtn').addEventListener('click', calculateConduit); calculateConduit(); // default calculation electrical conduit size calculator

let wireCount = 0; let wires = []; // store each wire object size, insulation function computeTotalArea() let total = 0; for (let

<hr> <h3>📘 Conduit Fill Reference Table (for common wires)</h3> <div style="overflow-x:auto;"> <table> <thead> <tr><th>Wire Size (AWG/kcmil)</th><th>THHN/THWN Area (in²)</th><th>XHHW Area (in²)</th><th>Trade Size 3/4" EMT (40% fill max area)</th></tr> </thead> <tbody> <tr><td>14 AWG</td><td>0.0097</td><td>0.0123</td><td>0.213 in²</td></tr> <tr><td>12 AWG</td><td>0.0133</td><td>0.0160</td><td>0.213 in²</td></tr> <tr><td>10 AWG</td><td>0.0211</td><td>0.0243</td><td>0.213 in²</td></tr> <tr><td>8 AWG</td><td>0.0366</td><td>0.0410</td><td>0.213 in²</td></tr> <tr><td>6 AWG</td><td>0.0507</td><td>0.0590</td><td>0.346 in² (1" EMT)</td></tr> <tr><td>4 AWG</td><td>0.0824</td><td>0.0937</td><td>0.598 in² (1¼" EMT)</td></tr> </tbody> </table> <p class="note" style="margin-top:8px;">⚠️ Full NEC Chapter 9 Table 4 & 5 used in calculator logic for 1/2" to 4" conduit.</p> </div> </div> function computeTotalArea() let total = 0

<script> // ---------- AREA DATABASE (sq inches) based on NEC Table 5 (THHN/THWN & XHHW approx) ---------- const wireAreas = // AWG sizes, compact "14": "THHN": 0.0097, "THWN": 0.0097, "XHHW": 0.0123 , "12": "THHN": 0.0133, "THWN": 0.0133, "XHHW": 0.0160 , "10": "THHN": 0.0211, "THWN": 0.0211, "XHHW": 0.0243 , "8": "THHN": 0.0366, "THWN": 0.0366, "XHHW": 0.0410 , "6": "THHN": 0.0507, "THWN": 0.0507, "XHHW": 0.0590 , "4": "THHN": 0.0824, "THWN": 0.0824, "XHHW": 0.0937 , "2": "THHN": 0.1158, "THWN": 0.1158, "XHHW": 0.1320 , "1": "THHN": 0.1562, "THWN": 0.1562, "XHHW": 0.1780 , "1/0": "THHN": 0.1855, "THWN": 0.1855, "XHHW": 0.2110 , "2/0": "THHN": 0.2223, "THWN": 0.2223, "XHHW": 0.2540 , "3/0": "THHN": 0.2679, "THWN": 0.2679, "XHHW": 0.3050 , "4/0": "THHN": 0.3195, "THWN": 0.3195, "XHHW": 0.3650 , "250": "THHN": 0.3970, "THWN": 0.3970, "XHHW": 0.4540 , "350": "THHN": 0.5242, "THWN": 0.5242, "XHHW": 0.6010 , "500": "THHN": 0.7073, "THWN": 0.7073, "XHHW": 0.8120 ;

<div class="result-panel"> <h3 style="margin-top:0;">📊 Result</h3> <div class="result-card"> <div id="resultArea"> <div class="conduit-size-result" style="background:#f1f5f9; color:#2d3e50;"> -- / -- </div> <div id="fillDetails"></div> </div> </div> <div class="warning" id="warningMsg" style="display:none;"></div> <div class="note"> <strong>⚡ NEC Fill Reference (typical):</strong> <ul style="margin:8px 0 0 16px; padding-left:0;"> <li>1 conductor → 53% max fill</li> <li>2 conductors → 31% max fill</li> <li>3+ conductors → 40% max fill</li> </ul> <small>*Based on standard THHN/THWN area values. Actual conduit fill depends on insulation and jamming rules.</small> </div> </div> </div>