Sheet metal gauge chart

A gauge number is not a thickness — it means something different in every metal. Pick the metal, then look up the gauge or type the thickness you have.

Metal

Full chart

Steel

Steel
Gauge	in	mm	lb/ft²
3/8″	.3750	9.52	15.683
5/16″	.3125	7.94	13.069
1/4″	.2500	6.35	10.455
3/16″	.1875	4.76	7.841
7 ga	.1793	4.55	7.498
8 ga	.1644	4.18	6.875
9 ga	.1495	3.80	6.252
10 ga	.1345	3.42	5.625
11 ga	.1196	3.04	5.002
12 ga	.1046	2.66	4.374
13 ga	.0897	2.28	3.751
14 ga	.0747	1.90	3.124
15 ga	.0673	1.71	2.814
16 ga	.0598	1.52	2.501
17 ga	.0538	1.37	2.250
18 ga	.0478	1.21	1.999
19 ga	.0418	1.06	1.748
20 ga	.0359	0.91	1.501
21 ga	.0329	0.84	1.376
22 ga	.0299	0.76	1.250
23 ga	.0269	0.68	1.125
24 ga	.0239	0.61	0.999
25 ga	.0209	0.53	0.874
26 ga	.0179	0.45	0.749
27 ga	.0164	0.42	0.686
28 ga	.0149	0.38	0.623
29 ga	.0135	0.34	0.565
30 ga	.0120	0.30	0.502

Manufacturers’ standard gauge for uncoated steel sheet. Weights are nominal; confirm against the mill certificate for the coil you are quoted.

Galvanized

Galvanized
Gauge	in	mm	lb/ft²
8 ga	.1681	4.27	7.030
9 ga	.1532	3.89	6.407
10 ga	.1382	3.51	5.780
11 ga	.1233	3.13	5.156
12 ga	.1084	2.75	4.533
13 ga	.0934	2.37	3.906
14 ga	.0785	1.99	3.283
15 ga	.0710	1.80	2.969
16 ga	.0635	1.61	2.656
17 ga	.0575	1.46	2.405
18 ga	.0516	1.31	2.158
19 ga	.0456	1.16	1.907
20 ga	.0396	1.01	1.656
21 ga	.0366	0.93	1.531
22 ga	.0336	0.85	1.405
23 ga	.0306	0.78	1.280
24 ga	.0276	0.70	1.154
25 ga	.0247	0.63	1.033
26 ga	.0217	0.55	0.907
27 ga	.0202	0.51	0.845
28 ga	.0187	0.47	0.782
29 ga	.0172	0.44	0.719
30 ga	.0157	0.40	0.657

Weights include the zinc coating, per published galvanized gauge tables.

Aluminum

Aluminum
Gauge	in	mm	lb/ft²
2″	2.000	50.8	28.080
1-1/2″	1.500	38.1	21.060
1-1/4″	1.250	31.8	17.550
1″	1.000	25.4	14.040
3/4″	.7500	19.05	10.530
5/8″	.6250	15.88	8.775
1/2″	.5000	12.70	7.020
3/8″	.3750	9.52	5.265
5/16″	.3125	7.94	4.388
1/4″	.2500	6.35	3.510
3 ga	.2294	5.83	3.221
4 ga	.2043	5.19	2.868
3/16″	.1875	4.76	2.633
5 ga	.1819	4.62	2.554
6 ga	.1620	4.11	2.274
7 ga	.1443	3.67	2.026
8 ga	.1285	3.26	1.804
1/8″	.1250	3.18	1.755
9 ga	.1144	2.91	1.606
10 ga	.1019	2.59	1.431
11 ga	.0907	2.30	1.273
12 ga	.0808	2.05	1.134
13 ga	.0720	1.83	1.011
14 ga	.0641	1.63	0.900
15 ga	.0571	1.45	0.802
16 ga	.0508	1.29	0.713
17 ga	.0453	1.15	0.636
18 ga	.0403	1.02	0.566
19 ga	.0359	0.91	0.504
20 ga	.0320	0.81	0.449
21 ga	.0285	0.72	0.400
22 ga	.0253	0.64	0.355
23 ga	.0226	0.57	0.317
24 ga	.0201	0.51	0.282

Weights are for 3003/5052 at 0.0975 lb/in³; 6061 runs marginally heavier.

Stainless

Stainless
Gauge	in	mm	lb/ft²
10 ga	.1406	3.57	5.851
11 ga	.1250	3.18	5.202
12 ga	.1094	2.78	4.553
13 ga	.0938	2.38	3.904
14 ga	.0781	1.98	3.250
15 ga	.0703	1.79	2.926
16 ga	.0625	1.59	2.601
17 ga	.0563	1.43	2.343
18 ga	.0500	1.27	2.081
19 ga	.0438	1.11	1.823
20 ga	.0375	0.95	1.561
21 ga	.0344	0.87	1.432
22 ga	.0313	0.80	1.303
23 ga	.0281	0.71	1.169
24 ga	.0250	0.64	1.040
25 ga	.0219	0.56	0.911
26 ga	.0187	0.47	0.778

Stainless steel sheet gauge. Weights are for 304 and 316 at 0.2890 lb/in³.

Guide to sheet metal gauge charts

Metal gauge charts are essential tools in construction, manufacturing and metal fabrication. Whether you're working with ferrous metals like steel or non-ferrous metals such as aluminum and copper, understanding gauge measurements is key to choosing the right material for your project.

This guide explains what a gauge is and why different metals use different gauge standards. The charts above list each gauge's thickness in inches and millimetres and its weight per square foot.

What is a metal gauge?

A metal gauge is a measurement standard for the thickness of sheet metal. The higher the gauge number, the thinner the sheet: 10 gauge steel is thicker than 20 gauge. The same gauge number means a different thickness from one metal to another, because steel, galvanized, stainless and aluminum each have their own gauge standard. 16 gauge steel (0.0598") is thicker than 16 gauge aluminum (0.0508").

Ferrous and non-ferrous gauge charts

Carbon steel uses the manufacturers' standard gauge. Galvanized sheet has its own gauge, which counts the zinc coating, so each gauge is slightly thicker than uncoated steel. Stainless steel 304 and 316 has a separate gauge. Aluminum uses the Brown & Sharpe (AWG) gauge, with fractional sizes for thicker sheet and plate.

Weights are nominal. Confirm thickness and weight against the mill certificate for the material you're quoted.