Wire Gauge Size Charts: AWG (American Wire Gauge), SWG (British Standard), IEC 60228

Contents

American Wire Gauge Size Chart (AWG)
AWG Chart for Copper Wire (Resistance / Ampacity / Fusing Current)
British Standard Wire Gauge Size Chart (SWG)
Comparison of AWG & IEC Wire Gauge Sizes
Strand make-up according to DIN VDE 0295, IEC 60228
Visual Comparison of AWG, SWG & IEC Wire Gauge Sizes

Wire gauge charts provide a reference for determining the diameter or thickness of wires, typically used in electrical and engineering applications. These charts are available for various wire gauge standards, including the American Wire Gauge (AWG), Standard Wire Gauge (SWG), and others. They display the gauge number alongside the corresponding diameter or thickness in inches or millimeters. Wire gauge charts are invaluable tools for selecting the appropriate wire size for specific purposes, ensuring compatibility and safety in electrical systems and other applications.

American Wire Gauge Size Chart (AWG)

The American Wire Gauge (AWG) is a standardized wire gauge system introduced in 1857, primarily utilized in North America to specify the diameters of round, solid, nonferrous, electrically conducting wires.

AWG	Diameter		Turns of wire, w/o insulation		Area
AWG	(in)	(mm)	(per in)	(per cm)	(kcmil)	(mm²)
0000 (4/0)	0.4600	11.684	2.17	0.856	212	107
000 (3/0)	0.4096	10.405	2.44	0.961	168	85.0
00 (2/0)	0.3648	9.266	2.74	1.08	133	67.4
0 (1/0)	0.3249	8.251	3.08	1.21	106	53.5
1	0.2893	7.348	3.46	1.36	83.7	42.4
2	0.2576	6.544	3.88	1.53	66.4	33.6
3	0.2294	5.827	4.36	1.72	52.6	26.7
4	0.2043	5.189	4.89	1.93	41.7	21.2
5	0.1819	4.621	5.50	2.16	33.1	16.8
6	0.1620	4.115	6.17	2.43	26.3	13.3
7	0.1443	3.665	6.93	2.73	20.8	10.5
8	0.1285	3.264	7.78	3.06	16.5	8.37
9	0.1144	2.906	8.74	3.44	13.1	6.63
10	0.1019	2.588	9.81	3.86	10.4	5.26
11	0.0907	2.305	11.0	4.34	8.23	4.17
12	0.0808	2.053	12.4	4.87	6.53	3.31
13	0.0720	1.828	13.9	5.47	5.18	2.62
14	0.0641	1.628	15.6	6.14	4.11	2.08
15	0.0571	1.450	17.5	6.90	3.26	1.65
16	0.0508	1.291	19.7	7.75	2.58	1.31
17	0.0453	1.150	22.1	8.70	2.05	1.04
18	0.0403	1.024	24.8	9.77	1.62	0.823
19	0.0359	0.912	27.9	11.0	1.29	0.653
20	0.0320	0.812	31.3	12.3	1.02	0.518
21	0.0285	0.723	35.1	13.8	0.810	0.410
22	0.0253	0.644	39.5	15.5	0.642	0.326
23	0.0226	0.573	44.3	17.4	0.509	0.258
24	0.0201	0.511	49.7	19.6	0.404	0.205
25	0.0179	0.455	55.9	22.0	0.320	0.162
26	0.0159	0.405	62.7	24.7	0.254	0.129
27	0.0142	0.361	70.4	27.7	0.202	0.102
28	0.0126	0.321	79.1	31.1	0.160	0.0810
29	0.0113	0.286	88.8	35.0	0.127	0.0642
30	0.0100	0.255	99.7	39.3	0.101	0.0509
31	0.00893	0.227	112	44.1	0.0797	0.0404
32	0.00795	0.202	126	49.5	0.0632	0.0320
33	0.00708	0.180	141	55.6	0.0501	0.0254
34	0.00630	0.160	159	62.4	0.0398	0.0201
35	0.00561	0.143	178	70.1	0.0315	0.0160
36	0.00500	0.127	200	78.7	0.0250	0.0127
37	0.00445	0.113	225	88.4	0.0198	0.0100
38	0.00397	0.101	252	99.3	0.0157	0.00797
39	0.00353	0.0897	283	111	0.0125	0.00632
40	0.00314	0.0799	318	125	0.00989	0.00501

The wire dimensions are outlined in ASTM standard B 258, with the cross-sectional area of each gauge serving as a critical determinant of its current-carrying capacity.

AWG employs a logarithmic stepped scale, with increasing gauge numbers corresponding to logarithmically decreasing wire diameters. This logarithmic progression aligns with other non-metric gauging systems like the British Standard Wire Gauge (SWG). However, AWG differs from the metric wire-size standard, IEC 60228, prevalent in most global regions, which bases measurements directly on the wire cross-sectional area in square millimeters (mm²).

AWG Chart for Copper Wire (Resistance / Ampacity / Fusing Current)

The following table presents diverse data, encompassing the resistance of different wire gauges and the permissible current (ampacity) for copper conductors with plastic insulation. The diameter specifications provided pertain to solid wires; for stranded wires, the equivalent cross-sectional copper area is computed.

Fusing current, indicative of the wire’s melting point, is approximated at a 25°C (77°F) ambient temperature. The table’s assumptions are based on DC currents or AC frequencies at or below 60 Hz, without factoring in the skin effect phenomenon.

AWG Copper wire	Length-specific resistance		Ampacity at temperature rating			Fusing current
	Length-specific resistance		60 °C	75 °C	90 °C	Preece	Onderdonk
	(mΩ/m)	(mΩ/ft)	(A)			~10 s	1 s	32 ms
0000 (4/0)	0.1608	0.0490	195	230	260	3.2 kA	33 kA	182 kA
000 (3/0)	0.2028	0.0618	165	200	225	2.7 kA	26 kA	144 kA
00 (2/0)	0.2557	0.0779	145	175	195	2.3 kA	21 kA	115 kA
0 (1/0)	0.3224	0.0982	125	150	170	1.9 kA	16 kA	91 kA
1	0.4066	0.1239	110	130	145	1.6 kA	13 kA	72 kA
2	0.5127	0.1563	95	115	130	1.3 kA	10.2 kA	57 kA
3	0.6465	0.1970	85	100	115	1.1 kA	8.1 kA	45 kA
4	0.8152	0.2485	70	85	95	946 A	6.4 kA	36 kA
5	1.028	0.3133				795 A	5.1 kA	28 kA
6	1.296	0.3951	55	65	75	668 A	4.0 kA	23 kA
7	1.634	0.4982				561 A	3.2 kA	18 kA
8	2.061	0.6282	40	50	55	472 A	2.5 kA	14 kA
9	2.599	0.7921				396 A	2.0 kA	11 kA
10	3.277	0.9989	30	35	40	333 A	1.6 kA	8.9 kA
11	4.132	1.260				280 A	1.3 kA	7.1 kA
12	5.211	1.588	20	25	30	235 A	1.0 kA	5.6 kA
13	6.571	2.003				198 A	798 A	4.5 kA
14	8.286	2.525	15	20	25	166 A	633 A	3.5 kA
15	10.45	3.184				140 A	502 A	2.8 kA
16	13.17	4.016			18	117 A	398 A	2.2 kA
17	16.61	5.064				99 A	316 A	1.8 kA
18	20.95	6.385	10	14	16	83 A	250 A	1.4 kA
19	26.42	8.051	—	—	—	70 A	198 A	1.1 kA
20	33.31	10.15	5	11	—	58.5 A	158 A	882 A
21	42.00	12.80	—	—	—	49 A	125 A	700 A
22	52.96	16.14	3	7	—	41 A	99 A	551 A
23	66.79	20.36	—	—	—	35 A	79 A	440 A
24	84.22	25.67	2.1	3.5	—	29 A	62 A	348 A
25	106.2	32.37	—	—	—	24 A	49 A	276 A
26	133.9	40.81	1.3	2.2	—	20 A	39 A	218 A
27	168.9	51.47	—	—	—	17 A	31 A	174 A
28	212.9	64.90	0.83	1.4	—	14 A	24 A	137 A
29	268.5	81.84	—	—	—	12 A	20 A	110 A
30	338.6	103.2	0.52	0.86	—	10 A	15 A	86 A
31	426.9	130.1	—	—	—	9 A	12 A	69 A
32	538.3	164.1	0.32	0.53	—	7 A	10 A	54 A
33	678.8	206.9	—	—	—	6 A	7.7 A	43 A
34	856.0	260.9	0.18	0.3	—	5 A	6.1 A	34 A
35	1079	329.0	—	—	—	4 A	4.8 A	27 A
36	1361	414.8	—	—	—	4 A	3.9 A	22 A
37	1716	523.1	—	—	—	3 A	3.1 A	17 A
38	2164	659.6	—	—	—	3 A	2.4 A	14 A
39	2729	831.8	—	—	—	2 A	1.9 A	11 A
40	3441	1049	—	—	—	1 A	1.5 A	8.5 A

While AWG and the Brown & Sharpe (B&S) sheet metal gauge are essentially identical, the latter was specifically designed for use with sheet metals, despite their functional interchangeability. The use of B&S terminology in reference to wire gauges is technically incorrect.

British Standard Wire Gauge Size Chart (SWG)

Below is a table listing gauge numbers alongside corresponding wire diameters. The system is based on the “thou” (or “mil” in US English), equivalent to 0.001 inches. Wire sizes are denoted as diameters in thou and tenths of a thou (mils and tenths). As gauge numbers increase, wire diameter decreases. For instance, the largest size, No. 7/0, measures 0.50 inches (500 thou or 12.7 mm) in diameter, while No. 1 is 0.30 inches (300 thou), and the smallest, No. 50, is 0.001 inches (1 thou or 25.4 µm).

The system exhibits an approximate exponential curve when plotting diameter against gauge number, with each size being roughly a constant multiple of the preceding size. The weight per unit length decreases by an average of about 20% with each step.

SWG	Diameter (in)	Diameter (mm)	Step
7/0	0.500	12.700	0.036″/gauge
6/0	0.464	11.786	0.032″/gauge
5/0	0.432	10.973	0.032″/gauge
4/0	0.400	10.160	0.028″/gauge
3/0	0.372	9.449	0.024″/gauge
2/0	0.348	8.839
0	0.324	8.230
1	0.300	7.620
2	0.276	7.010
3	0.252	6.401	0.020″/gauge
4	0.232	5.893
5	0.212	5.385
6	0.192	4.877	0.016″/gauge
7	0.176	4.470
8	0.160	4.064
9	0.144	3.658
10	0.128	3.251	0.012″/gauge
11	0.116	2.946
12	0.104	2.642
13	0.092	2.337
14	0.080	2.032	0.008″/gauge
15	0.072	1.829
16	0.064	1.626
17	0.056	1.422
18	0.048	1.219
19	0.040	1.016	0.004″/gauge
20	0.036	0.914
21	0.032	0.813
22	0.028	0.711
23	0.024	0.610	0.002″/gauge
24	0.022	0.559
25	0.020	0.5080
26	0.018	0.4572	0.0016″/gauge
27	0.0164	0.4166	0.0016″/gauge
28	0.0148	0.3759	0.0012″/gauge
29	0.0136	0.3454	0.0012″/gauge
30	0.0124	0.3150	0.0008″/gauge
31	0.0116	0.2946
32	0.0108	0.2743
33	0.0100	0.2540
34	0.0092	0.2337
35	0.0084	0.2134
36	0.0076	0.1930
37	0.0068	0.1727
38	0.0060	0.1524
39	0.0052	0.1321	0.0004″/gauge
40	0.0048	0.1219
41	0.0044	0.1118
42	0.004	0.1016
43	0.0036	0.0914
44	0.0032	0.0813
45	0.0028	0.0711
46	0.0024	0.0610
47	0.0020	0.0508
48	0.0016	0.0406
49	0.0012	0.0305	0.0002″/gauge
50	0.0010	0.0254	0.0002″/gauge

Since weight per unit length is proportional to the cross-sectional area, which in turn is related to the square of the diameter, the diameter decreases by approximately 10.6%. However, the system is piecewise linear and only loosely approximates the exponential curve. It progresses in constant steps of 0.4 thou (0.4 mil) within the range of No. 49 to No. 39, and 0.8 thou (0.8 mil) from No. 39 to No. 30.

Comparison of AWG & IEC Wire Gauge Sizes

American Wire Gauge (AWG) and IEC 60228 (mm2) wire sizes.

AWG	IEC (mm2)
30	0.05
28	0.08
26	0.14
24	0.25
22	0.34
21	0.38
20	0.50
18	0.75
17	1.00
16	1.50
14	2.50
12	4
10	6
8	10
6	16
4	25
2	35
1	50
2/0	70
3/0	95
4/0	120
300 MCM	150
350 MCM	185
500 MCM	240
600 MCM	300
750 MCM	400
1000 MCM	500

Strand make-up according to DIN VDE 0295, IEC 60228

Cross-section in mm²	Stranded Wires	Multi-Stranded Wires	Fine Wires	Extra-fine Wires
	class 2 DIN VDE 0295		class 5 DIN VDE 0295	class 6 DIN VDE 0295
	Number*** of Wires x Single Wire Ø in mm	Number of Wires x Single Wire Ø in mm	Number* of Wires** x Single Wire Ø in mm	Number* of Wires** x Single Wire Ø in mm	Number* of Wires x Single Wire Ø in mm	Number* of Wires x Single Wire Ø in mm	Number* of Wires x Single Wire Ø in mm
0.05						~14 x 0.07	~26 x 0.05
0.08							~40 x 0.05
0.09						~24 x 0.07
0.14			~18 x 0.1	~18 x 0.1	~18 x 0.1	~36 x 0.07	~72 x 0.05
0.25			~14 x 0.15	~32 x 0.1	~32 x 0.1	~65 x 0.07	~128 x 0.05
0.34		7 x 0.25	~19 x 0.15	~42 x 0.1	~42 x 0.1	~88 x 0.07	~174 x 0.05
0.38		7 x 0.27	~12 x 0.2	~21 x 0.15	~48 x 0.1	~100 x 0.07	~194 x 0.05
0.5	7 x 0.30	7 x 0.30	~16 x 0.2	~28 x 0.15	~64 x 0.1	~131 x 0.07	~256 x 0.05
0.75	7 x 0.37	7 x 0.37	~24 x 0.2	~42 x 0.15	~96 x 0.1	~195 x 0.07	~384 x 0.05
1.0	7 x 0.43	7 x 0.43	~32 x 0.2	~56 x 0.15	~128 x 0.1	~260 x 0.07	~512 x 0.05
1.5	7 x 0.52	7 x 0.52	~30 x 0.25	~84 x 0.15	~192 x 0.1	~392 x 0.07	~768 x 0.05
2.5	7 x 0.67	19 x 0.41	~50 x 0.25	~140 x 0.15	~320 x 0.1	~651 x 0.07	~1280 x 0.05
4	7 x 0.85	19 x 0.52	~56 x 0.3	~224 x 0.15	~512 x 0.1	~1040 x 0.07
6	7 x 1.05	19 x 0.64	~84 x 0.3	~192 x 0.2	~768 x 0.1	~1560 x 0.07
10	7 x 1.35	49 x 0.51	~80 x 0.4	~320 x 0.2	~1280 x 0.1	~2600 x 0.07
16	7 x 1.70	49 x 0.65	~128 x 0.4	~512 x 0.2	~2048 x 0.1
25	7 x 2.13	84 x 0.62	~200 x 0.4	~800 x 0.2	~3200 x 0.1
35	7 x 2.52	133 x 0.58	~280 x 0.4	~1120 x 0.2
50	19 x 1.83	133 x 0.69	~400 x 0.4	~705 x 0.3
70	19 x 2.17	189 x 0.69	~356 x 0.5	~990 x 0.3
95	19 x 2.52	259 x 0.69	~485 x 0.5	~1340 x 0.3
120	37 x 2.03	336 x 0.67	~614 x 0.5	~1690 x 0.3
150	37 x 2.27	392 x 0.69	~765 x 0.5	~2123 x 0.3
185	37 x 2.52	494 x 0.69	~944 x 0.5	~1470 x 0.4
240	61 x 2.24	627 x 0.70	~1225 x 0.5	~1905 x 0.4
300	61 x 2.50	790 x 0.70	~1530 x 0.5	~2385 x 0.4
400	61 x 2.89		~2035 x 0.5
500	61 x 3.23		~1768 x 0.6
630	91 x 2.97		~2228 x 0.6

^* The number of individual wires are without obligation.
^** The diameters of the single wires for each conductor are not allowed to exceed the values stated to DIN VDE 0295. The single wires of a stranded conductor must have all the same nominal diameters.
^*** Minimum-number of single wires of stranded conductor. The single wires of a stranded conductor must have all the same nominal diameters.

Visual Comparison of AWG, SWG & IEC Wire Gauge Sizes

Below is a comparison of wire gauge sizes according to the British Standard Wire Gauge (SWG), American Wire Gauge (AWG), and International Electrotechnical Commission (IEC) 60228 standard. Note that the gauge numbers and corresponding wire diameters may vary slightly depending on the specific standard or application.

Comparison of SWG (red), AWG (blue) and IEC 60228 (black) wire gauge sizes from 0.03 to 200 mm2 to scale on a 1 mm grid (in the SVG file, hover over a size to highlight it). SWG and AWG are commonly used in the UK and US, respectively, while IEC 60228 is an international standard.

Comments: 2

Andrew Harbert 02/26/2024 at 3:08 PM

Does this data depend heavily on the wire material? For example, what if I choose aluminum wire rather than copper?

1. Jonathan Field 02/27/2024 at 2:18 AM
  
  For different types of wires and materials, the dimensions may vary, for example for multi-core cables!

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