Wire Gauge Calculator
Calculate the correct AWG wire gauge for your application
Input Parameters
How It Works
This calculator uses the voltage drop formula: Vd = 2 × I × R × L / 1000
- • Vd = Voltage drop (volts)
- • I = Current (amperes)
- • R = Resistance per 1000 feet (ohms)
- • L = One-way cable length (feet)
- • Factor of 2 accounts for current flowing through both conductors
The calculator selects the smallest wire gauge that keeps voltage drop within your specified limit.
AWG Wire Gauge Reference
| AWG | Diameter (mm) | Resistance (Ω/1000ft) | Max Current (A) |
|---|---|---|---|
| 10 | 2.59 | 0.999 | 30 |
| 12 | 2.05 | 1.588 | 20 |
| 14 | 1.63 | 2.525 | 15 |
| 16 | 1.29 | 4.016 | 10 |
| 18 | 1.02 | 6.385 | 7 |
| 20 | 0.81 | 10.15 | 5 |
| 22 | 0.64 | 16.14 | 3 |
| 24 | 0.51 | 25.67 | 2 |
*Maximum current ratings are for reference only. Actual ampacity depends on installation conditions, temperature, and insulation type.