Wire Gauge Calculator

Look up the diameter and cross-sectional area of any AWG wire gauge, from 4/0 down to 30 AWG.

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AWG gauge

Result

AWG gauge

10 AWG

Diameter: 0.1019 in / 2.588 mm
Area (cmil): 10383.0
Area (mm²): 5.2612

How it works

American Wire Gauge (AWG) is defined by a geometric progression: each step of 3 gauge numbers roughly doubles or halves the wire's cross-sectional area. Diameter and area are computed directly from that definition, so these figures are exact — not looked up from a table.

AWG reference table

Resistance and ampacity columns aren't shown yet — they require transcribing NEC tables from a licensed copy, tracked in docs/CALCULATION-AUDIT.md.

AWG	Diameter (in)	Diameter (mm)	Area (cmil)	Area (mm²)
4/0	0.4600	11.684	211600.0	107.2193
3/0	0.4096	10.405	167806.4	85.0288
2/0	0.3648	9.266	133076.5	67.4309
1/0	0.3249	8.251	105534.5	53.4751
1 AWG	0.2893	7.348	83692.7	42.4077
2 AWG	0.2576	6.544	66371.3	33.6308
3 AWG	0.2294	5.827	52634.8	26.6705
4 AWG	0.2043	5.189	41741.3	21.1506
5 AWG	0.1819	4.621	33102.4	16.7732
6 AWG	0.1620	4.115	26251.4	13.3018
7 AWG	0.1443	3.665	20818.3	10.5488
8 AWG	0.1285	3.264	16509.7	8.3656
9 AWG	0.1144	2.906	13092.7	6.6342
10 AWG	0.1019	2.588	10383.0	5.2612
11 AWG	0.0907	2.305	8234.1	4.1723
12 AWG	0.0808	2.053	6529.9	3.3088
13 AWG	0.0720	1.828	5178.5	2.6240
14 AWG	0.0641	1.628	4106.7	2.0809
15 AWG	0.0571	1.450	3256.8	1.6502
16 AWG	0.0508	1.291	2582.7	1.3087
17 AWG	0.0453	1.150	2048.2	1.0378
18 AWG	0.0403	1.024	1624.3	0.8230
19 AWG	0.0359	0.912	1288.1	0.6527
20 AWG	0.0320	0.812	1021.5	0.5176
21 AWG	0.0285	0.723	810.1	0.4105
22 AWG	0.0253	0.644	642.4	0.3255
23 AWG	0.0226	0.573	509.5	0.2582
24 AWG	0.0201	0.511	404.0	0.2047
25 AWG	0.0179	0.455	320.4	0.1624
26 AWG	0.0159	0.405	254.1	0.1288
27 AWG	0.0142	0.361	201.5	0.1021
28 AWG	0.0126	0.321	159.8	0.0810
29 AWG	0.0113	0.286	126.7	0.0642
30 AWG	0.0100	0.255	100.5	0.0509

Important assumptions

Diameter and area are for bare solid conductors — stranded conductors of the same gauge have a slightly larger overall diameter.
This page does not yet recommend a gauge for a given load, and does not check ampacity — see the Voltage Drop and Wire Size calculators for that once their underlying data is verified.

FAQ

What does a lower AWG number mean?

Counterintuitively, a lower AWG number means a thicker wire. 10 AWG is thicker than 14 AWG. Above 1 AWG, sizes continue as 1/0, 2/0, 3/0, 4/0 — each getting progressively thicker.

How do I convert AWG to mm²?

Use the reference table above, or enter a gauge in the calculator — the mm² area is computed directly from the AWG geometric definition, exact to the precision shown.

Is stranded wire the same diameter as solid wire of the same gauge?

No. AWG defines the conductor's cross-sectional copper area, but a stranded conductor bundles multiple smaller strands with small gaps between them, so its overall (jacketed) diameter is somewhat larger than an equivalent solid conductor.

Related calculators

FigureDesk results are advisory and do not replace a licensed electrician, a qualified engineer, or the applicable local electrical code. Verify any electrical work against your local code and with a qualified professional before relying on it.