Convert an American Wire Gauge (AWG) number to the wire diameter and cross-section area. Enter the gauge, using -1, -2 and -3 for 2/0, 3/0 and 4/0. Free, private, and runs entirely in your browser.
The AWG scale is geometric. Each gauge number step changes the diameter by a fixed factor, and 39 steps from 36 to 0 span a ratio of 92. The diameter in millimeters is 0.127 times 92 raised to the power of (36 − n) ÷ 39.
What is the diameter of 12 AWG wire? About 2.05 mm (0.0808 in) with an area of 3.31 mm².
Does a bigger gauge number mean thicker wire? No. A larger AWG number means a thinner wire.
For 12 AWG, d = 0.127 × 92^(24 ÷ 39) ≈ 2.053 mm. The area is π ÷ 4 × 2.053² ≈ 3.31 mm², and the diameter is about 80.8 mils, so the area is about 6,530 circular mils.
How do I enter 4/0 wire? Enter -3 for 4/0, -2 for 3/0 and -1 for 2/0. 1/0 is gauge 0.
What are circular mils? A wire area unit equal to the square of the diameter in mils, used in the United States for large conductors.
The American Wire Gauge was established in 1857 by the Brown & Sharpe company and is still the standard for non-ferrous wire in North America. It is defined so that the diameter follows a geometric progression, with each gauge about 12.3% smaller than the one before, which makes the calculations in this converter exact.
Use this converter to identify a wire, to compare gauges with metric cross-sections, or to check a conductor listing. Always follow electrical codes and manufacturer data for current ratings, and use the voltage drop calculator to check long runs.
What is the metric equivalent of 14 AWG? About 2.08 mm², close to the 2.5 mm² size used in many countries, though the two are not identical.
How does gauge relate to resistance? Thinner wire has higher resistance per length. The voltage drop calculator uses that to find losses.