Wire & Sheet Gauge Chart

Convert AWG wire gauges and sheet-metal gauges to thickness (steel (Manufacturers’ Standard) and aluminium (Brown & Sharpe)) in inches and millimeters. Searchable, in your browser.

AWG wire gauge

AWGDiameter (in)Diameter (mm)
4/00.460011.684
3/00.409610.405
2/00.36489.266
1/00.32498.251
10.28937.348
20.25766.544
30.22945.827
40.20435.189
50.18194.621
60.16204.115
70.14433.665
80.12853.264
90.11442.906
100.10192.588
110.09072.305
120.08082.053
130.07201.828
140.06411.628
150.05711.450
160.05081.291
170.04531.150
180.04031.024
190.03590.912
200.03200.812
210.02850.723
220.02530.644
230.02260.573
240.02010.511
250.01790.455
260.01590.405
270.01420.361
280.01260.321
290.01130.286
300.01000.255
310.00890.227
320.00800.202
330.00710.180
340.00630.160
350.00560.143
360.00500.127
370.00450.113
380.00400.101
390.00350.090
400.00310.080

Sheet metal gauge thickness

GaugeSteel (in)Steel (mm)Aluminium (in)Aluminium (mm)
3 0.23916.073 0.22945.827
4 0.22425.695 0.20435.189
5 0.20925.314 0.18194.621
6 0.19434.935 0.16204.115
7 0.17934.554 0.14433.665
8 0.16444.176 0.12853.264
9 0.14953.797 0.11442.906
10 0.13453.416 0.10192.588
11 0.11963.038 0.09072.305
12 0.10462.657 0.08082.053
13 0.08972.278 0.07201.828
14 0.07471.897 0.06411.628
15 0.06731.709 0.05711.450
16 0.05981.519 0.05081.291
17 0.05381.367 0.04531.150
18 0.04781.214 0.04031.024
19 0.04181.062 0.03590.912
20 0.03590.912 0.03200.812
21 0.03290.836 0.02850.723
22 0.02990.759 0.02530.644
23 0.02690.683 0.02260.573
24 0.02390.607 0.02010.511
25 0.02090.531 0.01790.455
26 0.01790.455 0.01590.405
27 0.01640.417 0.01420.361
28 0.01490.378 0.01260.321
29 0.01350.343 0.01130.286
30 0.01200.305 0.01000.255

About wire & sheet gauge

Gauge numbers run backwards: a higher number means thinner material. Wire follows the American Wire Gauge (AWG) standard, where diameter = 0.005 × 92^((36 − n) ⁄ 39) inches. Sheet steel uses the Manufacturers' Standard Gauge, while sheet aluminium follows the Brown & Sharpe (AWG) system.

AWG diameter (in) = 0.005 × 92^((36 − n) ⁄ 39)

Different metals use different gauge standards, so the same gauge number is a different thickness in steel versus aluminium. Always match the gauge system to the material.

What this does

This chart converts AWG wire gauges and sheet-metal gauges to a thickness (steel by the Manufacturers’ Standard Gauge and aluminium by Brown & Sharpe (AWG)) in inches and millimeters.

How to use it

  1. Search or scroll to your gauge number.
  2. Pick the material (steel or aluminium).
  3. Read the thickness in inches and mm.

How it works

Gauge numbering runs backwards, a higher number is thinner, because it originally counted drawing steps. The same gauge is a different thickness in each metal: steel uses the Manufacturers’ Standard Gauge while aluminium follows Brown & Sharpe.

Understanding your result

Gauge numbers run backwards, so a higher gauge is thinner metal, and the same gauge differs between steel and aluminium because each uses its own standard. Always convert a gauge to an actual thickness in inches or millimetres before ordering or designing, rather than trusting the number alone.

Example

16-gauge steel sheet is about 0.0598 inch (1.52 mm), while 16 AWG aluminium wire is about 0.0508 inch (1.29 mm).

Sources & methodology

Last updated .

Frequently asked questions

Why is a higher gauge number thinner?

Gauge numbering runs backwards, it originally counted how many drawing steps the wire went through, so more steps (higher number) meant thinner material.

Why does the same gauge differ between metals?

Steel sheet uses the Manufacturers’ Standard Gauge while aluminium follows the Brown & Sharpe (AWG) system, so an identical gauge number is a different thickness in each metal.

Is my data stored?

No. Everything is calculated locally in your browser.