SWG

SWG - Standard Wire Gauge

Standard Wire Gauge (SWG) sizes were originally specified in BS 3737:1964. This is a withdrawn standard.

Sometimes it is known as Imperial Wire Gauge or British Standard Gauge.

SWG is a common measurement used in specifying thickness of wire, washers and plate.

SWG must not be confused with American Wire Gauge which is similar but not interchangeable numbering scheme.

The following table shows a comparison of standard wire gauge numbers and their inch and metric measurements.

Diameter Cross Sectional Area
SWG in mm mm2 Step
0000000 (7/0) 0.5000 12.700 126.6769 0.036"/gauge
000000 (6/0) 0.4640 11.786 109.0995 0.032"/gauge
00000 (5/0) 0.4320 10.973 94.5672
0000 (4/0) 0.4000 10.160 81.0732 0.028"/gauge
000 (3/0) 0.3720 9.449 70.1232 0.024"/gauge
00 (2/0) 0.3480 8.839 61.3615
0 0.3240 8.230 53.1973
1 0.3000 7.620 45.6037
2 0.2760 7.010 38.5945
3 0.2520 6.401 32.1800 0.020"/gauge
4 0.2320 5.893 27.2749
5 0.2120 5.385 22.7752
6 0.1920 4.877 18.6808 0.016"/gauge
7 0.1760 4.470 15.6930
8 0.1600 4.064 12.9717
9 0.1440 3.658 10.5094
10 0.1280 3.251 8.3009 0.012"/gauge
11 0.1160 2.946 6.8164
12 0.1040 2.642 5.4822
13 0.0920 2.337 4.2895
14 0.0800 2.032 3.2429 0.008"/gauge
15 0.0720 1.829 2.6273
16 0.0640 1.626 2.0765
17 0.0560 1.422 1.5881
18 0.0480 1.219 1.1671
19 0.0400 1.016 0.8107 0.004"/gauge
20 0.0360 0.914 0.6561
21 0.0320 0.813 0.5191
22 0.0280 0.711 0.3970
23 0.0240 0.610 0.2922 0.002"/gauge
24 0.0220 0.559 0.2454
25 0.0200 0.508 0.2027
26 0.0180 0.457 0.1642 0.0016"/gauge
27 0.0164 0.417 0.1363
28 0.0148 0.376 0.1110 0.0012"/gauge
29 0.0136 0.345 0.0937
30 0.0124 0.315 0.0779 0.0008"/gauge
31 0.0116 0.295 0.0682
32 0.0108 0.274 0.0591
33 0.0100 0.254 0.0507
34 0.0092 0.234 0.0429
35 0.0084 0.213 0.0358
36 0.0076 0.193 0.0293
37 0.0068 0.173 0.0234
38 0.0060 0.152 0.0182
39 0.0052 0.132 0.0137 0.0004"/gauge
40 0.0048 0.122 0.0117
41 0.0044 0.112 0.0098
42 0.0040 0.102 0.0081
43 0.0036 0.091 0.0066
44 0.0032 0.081 0.0052
45 0.0028 0.071 0.0040
46 0.0024 0.061 0.0029
47 0.0020 0.051 0.0020
48 0.0016 0.041 0.0013
49 0.0012 0.031 0.0007 0.0002"/gauge
50 0.0010 0.025 0.0005