AWG is a discrete gauge system; each standard gauge has a corresponding conductor cross-sectional area in mm². Circular mils (cmil) are another way of expressing conductor cross-sectional area.

AWG to mm and mm² Converter

Q: How do I convert AWG to mm?

Use the AWG diameter formula to find the conductor diameter in millimeters. This is the conductor itself, not insulation or finished cable diameter.

Q: How do I convert AWG to mm²?

Calculate the standard AWG conductor diameter, then calculate the circular cross-sectional area and convert it to mm².

Q: How do I convert mm or mm² to AWG?

Enter a conductor diameter or area; the converter selects the nearest supported AWG by conductor size and preserves your entered dimension.

Q: Does AWG measure wire diameter or cross-sectional area?

AWG is based on a standardized conductor diameter series. Cross-sectional area is derived from that diameter.

Q: Can I replace an AWG wire with the nearest metric wire size?

No. Dimensional similarity does not establish equivalent ampacity, code compliance, insulation rating, equipment compatibility or suitability as a replacement conductor.

Convert AWG to conductor diameter in millimeters, inches and mm², or identify the nearest standard AWG from a dimension.

AWG is a discrete wire-gauge system. This converter compares conductor diameter and cross-sectional area using the standard AWG formula.

Note: Diameter refers to the conductor itself, not the outside diameter of insulation or the finished cable. AWG-to-metric conversion compares conductor dimensions only; it does not determine ampacity, code compliance, insulation rating, equipment compatibility or safe substitution.

AWGExact AWG

Diameter (mm)

Diameter (in)

Area (mm²)

Circular mils (cmil)

Select an AWG size or enter a conductor diameter or cross-sectional area. The other values are calculated automatically, and dimensional inputs show the nearest standard AWG size.

You can type in any of the four measurement fields, including circular mils (cmil).

How AWG to mm and mm² Conversion Works

AWG identifies a wire size by a discrete gauge number. Each gauge corresponds to a conductor diameter in millimeters and inches, and that diameter converts to cross-sectional area in mm² or circular mils (cmil).

Diagram showing conductor diameter, cross-sectional area, and insulation excluded from the measurement.

Diameter (in) = 0.005 × 92^((36 − AWG) / 39)

Area (mm²) = π × diameter² / 4 × 645.16

Circular mils = (Diameter in inches × 1,000)²

1 cmil ≈ 0.000506707479 mm²

Examples

12 AWG to dimensions

12 AWG ≈ 2.0525 mm diameter ≈ 0.0808 in diameter ≈ 3.3088 mm² area

4 mm² to nearest AWG

4 mm² ≈ 2.2568 mm conductor diameter; nearest AWG by conductor size: 11 AWG

6,530 cmil to dimensions

6,530 cmil ≈ 3.3088 mm² and 2.0525 mm diameter; nearest AWG by conductor size: 12 AWG

Nearest AWG identifies conductor size only, not an electrical substitution recommendation.

AWG to Conductor Dimensions Table

AWG	Diameter (mm)	Diameter (in)	Area (mm²)	Circular mils (cmil)
4/0	11.6840	0.4600	107.2193	211,600
3/0	10.4049	0.4096	85.0288	167,806
2/0	9.2658	0.3648	67.4309	133,077
1/0	8.2515	0.3249	53.4751	105,535
1	7.3481	0.2893	42.4077	83,693
2	6.5437	0.2576	33.6308	66,371
4	5.1894	0.2043	21.1506	41,741
6	4.1154	0.1620	13.3018	26,251
8	3.2636	0.1285	8.3656	16,510
10	2.5882	0.1019	5.2612	10,383
12	2.0525	0.0808	3.3088	6,530
14	1.6277	0.0641	2.0809	4,107
16	1.2908	0.0508	1.3087	2,583
18	1.0237	0.0403	0.8230	1,624
20	0.8118	0.0320	0.5176	1,022
22	0.6438	0.0253	0.3255	642
24	0.5106	0.0201	0.2047	404
26	0.4049	0.0159	0.1288	254
28	0.3211	0.0126	0.0810	160
30	0.2546	0.0100	0.0509	101

Nearest AWG by Conductor Cross-Sectional Area

mm²	Nearest AWG
0.5	20 AWG
1.0	18 AWG
2.5	13 AWG
4.0	11 AWG
6.0	9 AWG
10.0	7 AWG
16.0	5 AWG
25.0	3 AWG

Frequently Asked Questions

What is AWG in mm²?

How do I convert AWG to mm?

How do I convert AWG to mm²?

How do I convert mm or mm² to AWG?

Does AWG measure wire diameter or cross-sectional area?

Can I replace an AWG wire with the nearest metric wire size?