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AWG wire gauge table (ASTM B258): 4/0 to 56 AWG, diameter in mils, inches and mm, area in circular mils and mm²

What is the diameter of 12 AWG, 14 AWG or 10 AWG wire in inches and mm? · Standard part · basis: ASTM B258 Table 1 (nominal diameters and cross-sectional areas of AWG solid round wires at 20 °C), all 60 rows as printed; numbers only

Also called: awg to mm, awg to mm2, 12 awg diameter, 14 awg wire diameter, 10 awg diameter mm, 18 awg wire diameter, awg wire size chart, awg to inches, 22 awg diameter, 24 awg wire diameter mm, wire gauge to mm, 20 awg diameter, 16 awg wire diameter, 0000 awg diameter, awg to circular mils, 26 awg diameter, 30 awg wire diameter, american wire gauge table, brown and sharpe gauge

Exact dimensions. Every file is drawn at true size with no tolerance added. The holes and pins that meet another part are listed below under Mating features, with the fit each joint needs; open those by your process's clearance before making the part. Mating features

sizes: 60 in table

Notes

ASTM B258 Table 1: standard nominal diameters and cross-sectional areas of AWG sizes of solid round wire at 20 °C, 4/0 to 56 AWG, as printed in the iTeh sample of ASTM B258-02. One mil is 0.001 in. The inch column is the mil value divided by 1000 (the standard prints mils and mm); the other columns are as printed. Per the standard, 4/0 to 44 AWG diameters are given to no more than four significant figures and 0.1 mil, 45 to 56 AWG to 0.01 mil; diameters are calculated from the AWG law and rounded only at the end.
Xem check: the printed mil values for 4/0 to 44 agree with the AWG law d = 0.005 in × 92^((36 − n) / 39) (n is the gauge number, with 1/0 = 0, 2/0 = -1, 3/0 = -2, 4/0 = -3) to within the standard's rounding, and every mm value but one (flagged below) equals mils × 0.0254 within its rounding. Each step down in gauge number is a factor of 92^(1/39) = 1.1229 in diameter; six gauges halve the diameter (about) and three gauges halve the area.
One printed value is inconsistent: the sample's mm diameter for 19 AWG is 0.904, but its own 35.9 mils is 0.912 mm and its area 0.653 mm² is that of a 0.912 mm wire (a 0.904 mm wire would be 0.642 mm²). The printed number is kept and flagged in the table; use 0.912 mm unless you have the standard in hand. Those are the solid conductor sizes. A stranded conductor of the same AWG has a larger overall diameter (7 strands = three strand diameters across, 19 strands = five, 37 = seven, and so on) and the strand diameters are in the stranding standards, not in B258. Insulated outside diameters differ by insulation type and maker: no maker-published table that could be read is on this page. Sized tubes for wires are on the heat-shrink and cable-gland pages.
A different series: SWG (British) and metric mm² sizes are on their own pages; sheet metal gauge numbers are not wire gauge numbers (the aluminium and brass sheet gauge uses the same AWG / Brown & Sharpe diameters, steel sheet gauge does not).
The standard is sold by ASTM; the table here is the one in the sample the publisher gives out. No files: wire is a plain cylinder.

AWG wire gauge table (ASTM B258): 4/0 to 56 AWG, diameter in mils… size chart

AWG	diameter (mils)	diameter (in, mils ÷ 1000)	diameter (mm)	area (circular mils)	area (mm²)
4/0	460.0	0.4600	11.684	211600	107.2
3/0	409.6	0.4096	10.404	167800	85.0
2/0	364.8	0.3648	9.26	133100	67.4
1/0	324.9	0.3249	8.25	105600	53.5
1	289.3	0.2893	7.35	83690	42.4
2	257.6	0.2576	6.54	66360	33.6
3	229.4	0.2294	5.82	52620	26.7
4	204.3	0.2043	5.19	41740	21.1
5	181.9	0.1819	4.62	33090	16.8
6	162.0	0.1620	4.11	26240	13.3
7	144.3	0.1443	3.67	20820	10.6
8	128.5	0.1285	3.26	16510	8.37
9	114.4	0.1144	2.91	13090	6.63
10	101.9	0.1019	2.59	10380	5.26
11	90.7	0.0907	2.30	8230	4.17
12	80.8	0.0808	2.05	6530	3.31
13	72.0	0.0720	1.83	5180	2.63
14	64.1	0.0641	1.63	4110	2.08
15	57.1	0.0571	1.45	3260	1.65
16	50.8	0.0508	1.29	2580	1.31
17	45.3	0.0453	1.15	2050	1.04
18	40.3	0.0403	1.02	1620	0.823
19	35.9	0.0359	0.904 (as printed; mils × 0.0254 = 0.912)	1290	0.653
20	32.0	0.0320	0.813	1020	0.519
21	28.5	0.0285	0.724	812	0.412
22	25.3	0.0253	0.643	640	0.324
23	22.6	0.0226	0.574	511	0.259
24	20.1	0.0201	0.511	404	0.205
25	17.9	0.0179	0.455	320	0.162
26	15.9	0.0159	0.404	253	0.128
27	14.2	0.0142	0.361	202	0.102
28	12.6	0.0126	0.320	159	0.0804
29	11.3	0.0113	0.287	128	0.0647
30	10.0	0.0100	0.254	100	0.0507
31	8.9	0.0089	0.226	79.2	0.0401
32	8.0	0.0080	0.203	64.0	0.0324
33	7.1	0.0071	0.180	50.4	0.0255
34	6.3	0.0063	0.160	39.7	0.0201
35	5.6	0.0056	0.142	31.4	0.0159
36	5.0	0.0050	0.127	25.0	0.0127
37	4.5	0.0045	0.114	20.2	0.0103
38	4.0	0.0040	0.102	16.0	0.00811
39	3.5	0.0035	0.0890	12.2	0.00621
40	3.1	0.0031	0.0787	9.61	0.00487
41	2.8	0.00280	0.0711	7.84	0.00397
42	2.5	0.00250	0.0635	6.25	0.00317
43	2.2	0.00220	0.0559	4.84	0.00245
44	2.0	0.00200	0.0508	4.00	0.00203
45	1.76	0.00176	0.0447	3.10	0.00157
46	1.57	0.00157	0.0399	2.46	0.00125
47	1.40	0.00140	0.0356	1.96	0.000993
48	1.24	0.00124	0.0315	1.54	0.000779
49	1.11	0.00111	0.0282	1.23	0.000624
50	0.99	0.00099	0.0252	0.980	0.000497
51	0.88	0.00088	0.0224	0.774	0.000392
52	0.78	0.00078	0.0198	0.608	0.000308
53	0.70	0.00070	0.0178	0.490	0.000248
54	0.62	0.00062	0.0158	0.384	0.000195
55	0.55	0.00055	0.0140	0.302	0.000153
56	0.49	0.00049	0.0125	0.240	0.000122

Mating features

Drawn at the exact size. Open press, slide, run and socket features by your process's clearance (tolerances by process); leave designed gaps and clamp fits as drawn.

feature	exact	mates with	fit	files
solid wire of a given AWG	diameter per the table, 20 °C (12 AWG 2.05 mm, 14 AWG 1.63 mm, 18 AWG 1.02 mm)	a clamp terminal, ferrule or crimp barrel sized for that AWG (the terminal maker's table governs)	designed	all

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

ASTM (iTeh sample copy)	ASTM B258-02: Table 1, standard nominal diameters and cross-sectional areas of AWG sizes of solid round wires at 20 C, 4/0 to 56	web	Publisher's page; dimensions are facts
ASTM	ASTM B258 Standard Specification for Standard Nominal Diameters and Cross-Sectional Areas of AWG Sizes of Solid Round Wires Used as Electrical Conductors	web	Standards body's page; dimensions are facts

Xem scan

File coming

No downloadable true-size file yet: the published figures do not fix the whole shape, and Xem never guesses a number. A measured scan is planned; request it and it moves up.

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Plain text: sheet.txt · JSON: /api/geometry?object=awg-wire-gauge-table-astm-b258

Schematic, not to scale.