Sheet Metal Gauge Calculator
Convert gauge to mm/inch and get sheet weight — steel, stainless, aluminum, galvanized. Free.
Pick a material and gauge number to see the exact thickness in mm and inches, or enter a measured thickness to find the nearest gauge. Add sheet size to get the weight per sheet instantly.
Sheet metal gauge chart (mm & inches)
| Gauge | Steel (mm) | Galvanized (mm) | Stainless (mm) | Aluminum (mm) | Steel (inch) |
|---|---|---|---|---|---|
| 3 | 6.073 | 6.073 | 6.35 | 5.827 | 0.2391 |
| 4 | 5.695 | 5.695 | 5.95 | 5.189 | 0.2242 |
| 5 | 5.314 | 5.314 | 5.55 | 4.620 | 0.2092 |
| 6 | 4.935 | 4.935 | 5.16 | 4.115 | 0.1943 |
| 7 | 4.554 | 4.554 | 4.76 | 3.665 | 0.1793 |
| 8 | 4.176 | 4.176 | 4.37 | 3.264 | 0.1644 |
| 9 | 3.797 | 3.797 | 3.97 | 2.906 | 0.1495 |
| 10 | 3.416 | 3.510 | 3.57 | 2.588 | 0.1345 |
| 11 | 3.038 | 3.132 | 3.18 | 2.304 | 0.1196 |
| 12 | 2.657 | 2.743 | 2.78 | 2.053 | 0.1046 |
| 13 | 2.278 | 2.413 | 2.38 | 1.803 | 0.0897 |
| 14 | 1.897 | 2.108 | 1.98 | 1.628 | 0.0747 |
| 15 | 1.704 | 1.905 | 1.83 | 1.448 | 0.0671 |
| 16 | 1.519 | 1.702 | 1.65 | 1.290 | 0.0598 |
| 17 | 1.367 | 1.498 | 1.47 | 1.151 | 0.0538 |
| 18 | 1.214 | 1.295 | 1.25 | 1.024 | 0.0478 |
| 19 | 1.067 | 1.147 | 1.09 | 0.912 | 0.0420 |
| 20 | 0.958 | 1.016 | 0.95 | 0.813 | 0.0377 |
| 21 | 0.841 | 0.902 | 0.87 | 0.723 | 0.0331 |
| 22 | 0.756 | 0.815 | 0.79 | 0.644 | 0.0298 |
| 23 | 0.662 | 0.728 | 0.69 | 0.573 | 0.0261 |
| 24 | 0.560 | 0.635 | 0.60 | 0.511 | 0.0220 |
| 25 | 0.508 | 0.559 | 0.55 | 0.455 | 0.0200 |
| 26 | 0.452 | 0.511 | 0.47 | 0.405 | 0.0178 |
| 27 | 0.409 | 0.462 | 0.44 | 0.361 | 0.0161 |
| 28 | 0.368 | 0.417 | 0.41 | 0.321 | 0.0145 |
| 29 | 0.341 | 0.384 | 0.36 | 0.286 | 0.0134 |
| 30 | 0.305 | 0.343 | 0.32 | 0.255 | 0.0120 |
FAQ
Why do gauge numbers run backwards?
The gauge system dates to wire drawing: a higher number means more passes through the die, so thinner material. 10 gauge steel is 3.4 mm while 26 gauge is 0.45 mm.
Is gauge the same for all metals?
No — gauge tables differ between steel, stainless, galvanized steel and aluminum. A 16-gauge aluminum sheet is thinner (1.29 mm) than 16-gauge steel (1.52 mm). The calculator uses each material's own table.
Gauge or mm — which should I order?
Metric thickness removes ambiguity. If your supplier works in gauge, always confirm the mm equivalent from their table before cutting or bending.
How thick is 16 gauge steel in inches?
16 gauge mild steel is 1.519 mm = 0.0598 inch (≈ 1/16"). 22 gauge is 0.756 mm = 0.0298 inch. See the full chart above for every gauge from 3 to 30.