Convert standard steel sheet-metal gauge to thickness in inches and millimeters.
Metal • gauge
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Sheet-metal thickness is specified by "gauge", where a higher gauge number means a thinner sheet — and the actual thickness differs by metal. This chart gives standard (uncoated) steel gauge in both inches and millimeters.
Fabricators, HVAC installers, auto-body workers and DIYers use it to read drawings and order the right material. Note that aluminum and stainless steel use slightly different gauge thicknesses than the steel values shown.