AWG and SWG Wire Gauge Converter

AWG and SWG wire gauge tables in mm, inches and mm², with the nearest AWG for each SWG size and a note on why the two systems differ.

AWG chart

American Wire Gauge, 0000 to 40, calculated from the AWG definition. Resistance is annealed copper at 20 °C.

AWG	Diameter (mm)	Diameter (in)	Area (mm²)	Resistance (Ω/km)
0000	11.684	0.46	107.219	0.16
000	10.405	0.4096	85.029	0.2
00	9.266	0.3648	67.431	0.26
0	8.251	0.3249	53.475	0.32
1	7.348	0.2893	42.408	0.41
2	6.544	0.2576	33.631	0.51
3	5.827	0.2294	26.67	0.65
4	5.189	0.2043	21.151	0.82
5	4.621	0.1819	16.773	1.03
6	4.115	0.162	13.302	1.3
7	3.665	0.1443	10.549	1.63
8	3.264	0.1285	8.366	2.06
9	2.906	0.1144	6.634	2.6
10	2.588	0.1019	5.261	3.28
11	2.305	0.0907	4.172	4.13
12	2.053	0.0808	3.309	5.21
13	1.828	0.072	2.624	6.57
14	1.628	0.0641	2.081	8.29
15	1.45	0.0571	1.65	10.45
16	1.291	0.0508	1.309	13.17
17	1.15	0.0453	1.038	16.61
18	1.024	0.0403	0.823	20.95
19	0.912	0.0359	0.653	26.41
20	0.812	0.032	0.518	33.31
21	0.723	0.0285	0.41	42
22	0.644	0.0253	0.326	52.96
23	0.573	0.0226	0.258	66.78
24	0.511	0.0201	0.205	84.21
25	0.455	0.0179	0.162	106.19
26	0.405	0.0159	0.129	133.9
27	0.361	0.0142	0.102	168.85
28	0.321	0.0126	0.081	212.92
29	0.286	0.0113	0.064	268.48
30	0.255	0.01	0.051	338.55
31	0.227	0.0089	0.04	426.9
32	0.202	0.008	0.032	538.32
33	0.18	0.0071	0.025	678.8
34	0.16	0.0063	0.02	855.96
35	0.143	0.0056	0.016	1079.34
36	0.127	0.005	0.013	1361.02
37	0.113	0.0045	0.01	1716.22
38	0.101	0.004	0.008	2164.11
39	0.09	0.0035	0.006	2728.89
40	0.08	0.0031	0.005	3441.07

SWG chart

Imperial Standard Wire Gauge, 7/0 to 50, from the published diameter table. Check the values against your own edition of the standard before relying on them for an order.

SWG	Diameter (mm)	Diameter (in)	Area (mm²)	Nearest AWG by area
7/0	12.7	0.5	126.6769	outside AWG 0000 to 40
6/0	11.786	0.464	109.0921	0000
5/0	10.973	0.432	94.5638	000
4/0	10.16	0.4	81.0732	000
3/0	9.449	0.372	70.1202	00
2/0	8.839	0.348	61.3643	00
1/0	8.23	0.324	53.1921	0
1	7.62	0.3	45.6037	1
2	7.01	0.276	38.5989	1
3	6.401	0.252	32.178	2
4	5.893	0.232	27.273	3
5	5.385	0.212	22.7735	4
6	4.877	0.192	18.6793	5
7	4.47	0.176	15.6958	5
8	4.064	0.16	12.9717	6
9	3.658	0.144	10.5071	7
10	3.251	0.128	8.3019	8
11	2.946	0.116	6.8183	9
12	2.642	0.104	5.4805	10
13	2.337	0.092	4.2888	11
14	2.032	0.08	3.2429	12
15	1.829	0.072	2.6268	13
16	1.626	0.064	2.0755	14
17	1.422	0.056	1.589	15
18	1.219	0.048	1.1675	16
19	1.016	0.04	0.8107	18
20	0.914	0.036	0.6567	19
21	0.813	0.032	0.5189	20
22	0.711	0.028	0.3973	21
23	0.61	0.024	0.2919	22
24	0.559	0.022	0.2452	23
25	0.508	0.02	0.2027	24
26	0.457	0.018	0.1642	25
27	0.417	0.0164	0.1363	26
28	0.376	0.0148	0.111	27
29	0.345	0.0136	0.0937	27
30	0.315	0.0124	0.0779	28
31	0.295	0.0116	0.0682	29
32	0.274	0.0108	0.0591	29
33	0.254	0.01	0.0507	30
34	0.234	0.0092	0.0429	31
35	0.213	0.0084	0.0358	32
36	0.193	0.0076	0.0293	32
37	0.173	0.0068	0.0234	33
38	0.152	0.006	0.0182	34
39	0.132	0.0052	0.0137	36
40	0.122	0.0048	0.0117	36
41	0.112	0.0044	0.0098	37
42	0.102	0.004	0.0081	38
43	0.091	0.0036	0.0066	39
44	0.081	0.0032	0.0052	40
45	0.071	0.0028	0.004	outside AWG 0000 to 40
46	0.061	0.0024	0.0029	outside AWG 0000 to 40
47	0.051	0.002	0.002	outside AWG 0000 to 40
48	0.041	0.0016	0.0013	outside AWG 0000 to 40
49	0.03	0.0012	0.0007	outside AWG 0000 to 40
50	0.025	0.001	0.0005	outside AWG 0000 to 40

SWG and AWG are different systems

Both count sizes with a number, and a higher number is a thinner wire, but the diameters are not the same. Do not swap one for the other without checking the table.

Frequently asked questions

Is SWG the same as AWG?

No. The same number gives a different wire. SWG 18 is 1.219 mm across and AWG 18 is 1.024 mm. Always state which system a drawing or order uses.

How is AWG calculated and SWG found?

AWG follows a formula: d = 0.127 mm × 92^((36 − n) / 39). SWG is a published table of diameters in inches, so it has no formula.

Which is used for cables?

IEC cable sizes are in mm². AWG is used in North American practice and SWG in older British and Commonwealth wire and winding data.

Length Converter Area Converter AWG to mm² calculator Conversion Centre