Wire Gauge Calculator for Electrical Installations
Calculate wire gauge (AWG) requirements for electrical installations based on current, voltage drop, and distance.
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Calculate wire gauge (AWG) requirements for electrical installations based on current, voltage drop, and distance.
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Enter Current, Voltage, Distance, and Maximum Voltage Drop %
Typical maximum: 3% for branch circuits, 5% total (NEC guidance)
| AWG | Diameter (mm) | Area (mm²) | Ampacity (A) |
|---|---|---|---|
| 14 | 1.628 | 2.081 | 15 |
| 12 | 2.053 | 3.307 | 20 |
| 10 | 2.588 | 5.261 | 30 |
| 8 | 3.264 | 8.367 | 40 |
| 6 | 4.115 | 13.300 | 55 |
| 4 | 5.189 | 21.150 | 70 |
| 2 | 6.544 | 33.620 | 95 |
| 1 | 7.348 | 42.410 | 110 |
| 0 | 8.251 | 53.490 | 125 |
Never exceed wire ampacity ratings. Undersized wires can overheat and cause fires.
Most electrical codes limit voltage drop to 3% for branch circuits, 5% total.
Size conductors by current, distance, and allowable voltage drop. Supports DC, single‑phase and three‑phase AC with optional reactance and derating.
Size copper or aluminum conductors by load, run length, and allowable drop. DC, 1‑phase, and 3‑phase supported.
Pick gauge or compute recommended size.
Power factor and reactance inputs.
Ambient and bundling factor support.
Important: This wire gauge calculator is designed for educational and preliminary electrical planning purposes using standard wire sizing tables and established electrical engineering principles. While calculations are based on recognized electrical standards and typical ampacity ratings, actual wire sizing involves complex factors including ambient temperature, conduit fill, voltage drop, installation methods, and specific electrical codes that require professional electrical analysis. For electrical installations, system design, safety assessments, or code compliance, always follow applicable electrical codes (NEC, local codes), consult licensed electricians, and obtain proper electrical permits and inspections to ensure safe and compliant electrical work for your specific installation requirements.
Input the maximum current that will flow through the wire in amperes.
Enter the system voltage and the length of wire run to calculate voltage drop.
Select copper or aluminum conductor based on your application and budget.
Enter acceptable voltage drop percentage (typically 3% for branch circuits, 5% total).
Get the minimum required AWG size and verify it meets both ampacity and voltage drop requirements.
The minimum AWG size that meets both current-carrying capacity and voltage drop requirements. Always use this size or larger.
Calculated voltage drop is within acceptable limits (typically <3% for branch circuits). Good electrical performance expected.
Voltage drop exceeds recommended limits. Consider larger wire size to improve efficiency and prevent equipment problems.
Current exceeds wire's safe carrying capacity. Must use larger wire size to prevent overheating and fire hazard.
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