Wire Gauge Conversions

AWG to mm²

AWG	mm²

36	0.013
34	0.020
32	0.032
30	0.051
28	0.081
26	0.129
24	0.205
22	0.326
20	0.518
18	0.823
16	1.309
14	2.081
12	3.309
10	5.261
8	8.366
6	13.302
4	21.151
2	33.361
1	42.408
1/0	53.475
2/0	67.431
3/0	85.029
4/0	107.219

mm² to AWG

mm²	AWG

0.13	25.959
0.25	23.139
0.35	21.687
0.5	20.149
0.75	18.401
1	17.160
1.2	16.374
1.5	15.412
1.75	14.747
2	14.171
2.5	13.209
4	11.182
6	9.433
8	8.193
10	7.230
12	6.444
16	5.204
25	3.279
35	1.828
50	0.710/0
70	2.161/0
95	3.478/0
120	4.486/0

Explanation

A lot of wire size conversion tables out there are completely incorrect. Many label 1 AWG as 50 mm², even though it's not even close to that. This page uses the actual equations to give the correct conversions.

Here's how it works: solid 36 AWG wire is defined as 0.005 inches in diameter, and solid 4/0 wire is defined as 0.46 inches in diameter. A smaller gauge number increases the wire diameter by a constant factor. This leads to the following equation, where d is the diameter of the wire, and n is the wire gauge in AWG:

$https://latex.codecogs.com/svg.image?\large d = 0.005 \textrm{ in} \times 92^{(36-n)/39}= 0.127 \textrm{ mm} \times 92^{(36-n)/39}$

Using the formula for a circle's area, we get the following equation, where A is the cross-sectional area in mm²:

$https://latex.codecogs.com/svg.image?\large A = \frac{0.127^{2} \pi}{4} \times 92^{(36-n)/19.5} \approx 0.012668 \times 92^{(36-n)/19.5}$

To convert from mm² to AWG, we can just invert the equation:

$https://latex.codecogs.com/svg.image?\large n = 36-19.5\log_{92}\left( \frac{4A}{0.127\textsuperscript{2} \pi} \right) \approx 36- 19.5\log_{92}\left( \frac{A}{0.012668} \right)$

Solid and stranded wires of the same gauge have the same cross-sectional area, so these conversions work with both solid and stranded wire.