About Wire Gauge Calculator
American Wire Gauge (AWG) is a standard set of wire sizes in which a larger number means a thinner wire. The diameter of gauge n is 0.127 mm × 92 raised to the power (36 − n) ÷ 39, so every 6 gauges halve the diameter and every 3 gauges halve the area. Resistance uses annealed copper at 20 °C, 0.017241 Ω·mm²/m. Safe current depends on insulation, bundling, and the local electrical code, so no ampacity is given.
How to use Wire Gauge Calculator
- Fill in "AWG size" and "Wire length for total resistance".
- The result appears below and updates as you type.
- Copy the result with the copy button, or download it as a file where that is offered.
Questions about Wire Gauge Calculator
What is the difference between AWG and mm²?
AWG is a gauge number based on wire diameter and is used mainly in North America. Most other countries specify the cross-section area in square millimetres. AWG 12 is about 3.31 mm², close to the 4 mm² and 2.5 mm² metric sizes.
Runs in your browser. Page last updated .