Sheet metal gauge chart
Gauge numbers mean different thicknesses for different metals. 16 gauge steel is 0.0598". 16 gauge stainless is 0.0625". 16 gauge aluminum is 0.0508". This chart has all four standards side by side so you stop guessing.
Updated September 2026
Quick answer
Gauge numbers mean different thicknesses for different metals. 16 gauge steel is 0.0598", 16 gauge stainless is 0.0625", and 16 gauge aluminum is 0.0508". Steel uses the Manufacturer's Standard Gauge, stainless a fractional-inch standard, and aluminum the Brown & Sharpe gauge. Always name the metal with the gauge, and call out exact thickness in inches or mm on the order.
Gauge to thickness in inches
Steel uses the Manufacturer's Standard Gauge (MSG). Stainless steel uses its own fractional-inch standard. Aluminum uses Brown & Sharpe (same as AWG). Galvanized adds zinc coating thickness to MSG.
Sources: Manufacturers' Standard Gauge for sheet steel (an industry convention that grew out of the 1893 US Standard Gauge, not an ASTM standard), Brown & Sharpe / AWG for aluminum. Galvanized includes zinc coating on both sides. Stainless uses the traditional fractional-inch-based gauge standard used by most suppliers and fabricators.
Gauge to weight per square foot
Thickness from the chart above times 40.84 lb/ft² per inch for mild steel, 41.62 for 304 stainless, and 14.04 for 6061 aluminum. Same math as the plate calculators.
Steel weights use 40.84lb/ft² per inch, so they run about 2% under the old MSG nominal weights, which used 41.82. Galvanized is left out because the zinc coating weighs differently from the steel under it.
Gauge to thickness in millimeters
Need the weight, not just the thickness?
This chart gives you the thickness. To get the weight of a specific piece, use the calculator for your material:
Questions welders keep asking
Why does the same gauge number mean different thicknesses for different metals?
Because each metal uses a different gauge standard. Carbon steel uses the Manufacturers' Standard Gauge (MSG). It comes from the 1893 US Standard Gauge, which set each gauge by weight per square foot; MSG turns those weights into thickness at 41.82 lb per square foot per inch. Stainless steel uses its own standard based on fractional-inch increments. Aluminum uses the Brown & Sharpe gauge (same as American Wire Gauge). Galvanized steel uses the MSG system but adds thickness for the zinc coating. The takeaway: always specify the metal when calling out a gauge.
What gauge is 1/8 inch steel?
11 gauge is the closest. 11 gauge steel is 0.1196 inches, which is about 4% thinner than a true 1/8" (0.125). If you need exactly 1/8" thick steel, call out the thickness in inches or millimeters on the order, not the gauge number.
What is the most common gauge for sheet metal fabrication?
16 gauge and 18 gauge are the workhorses. 16 gauge steel (0.0598") is thick enough for structural brackets, enclosures, and equipment panels. 18 gauge (0.0478") is the standard for ductwork, light enclosures, and decorative metalwork. Thinner than 20 gauge is mostly for flashing, trim, and non-structural applications.
Is 14 gauge stainless thicker than 14 gauge steel?
Yes. 14 gauge stainless is 0.0781" (5/64") while 14 gauge steel is 0.0747". That is about 4.5% thicker. This catches people off guard when they switch between materials. The stainless gauge standard uses fractional-inch-based values, while the steel MSG standard was derived from weight per square foot.
How do you convert gauge to weight per square foot?
Look up the thickness in inches from the chart, then multiply by the density constant: 40.84 for mild steel, 41.62 for 304 stainless, 14.04 for 6061 aluminum. Example: 16 gauge steel = 0.0598" × 40.84 = 2.44 lb/ft². MSG itself was built on 41.82 lb/ft² per inch, which is why older charts list 16 gauge at an even 2.50 lb/ft². The weight table above does the math for every gauge.
Weight is only half of material cost. To turn these pounds into a number you can quote, run the weld cost calculator for wire, gas, and labor per inch, or the job pricing calculator to build the whole bid.
Other metal weight calculators
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A36 mild steel. Every thickness from 1/16 up.
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Aluminum Plate Weight
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Aluminum Square Tube Weight
6061 square HSS by outside size and wall.
Aluminum Angle Weight
6061 equal-leg angle by leg and thickness.
Aluminum Flat Bar Weight
6061 flat bar by width and thickness.
Aluminum Round Bar Weight
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Stainless Plate Weight
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Stainless Square Tube Weight
304/316 square HSS by outside size and wall.
Stainless Angle Weight
304/316 equal-leg angle by leg and thickness.
Stainless Round Bar Weight
304/316 stainless round bar by diameter.
Plate Weight Chart
Weight per square foot by thickness. Steel, stainless, aluminum.
Pipe Weight Chart
Weight per foot by NPS and schedule. Sch 40, 80, XXS.
Schedule 40 Pipe Weight
Sch 40 lb/ft and kg/m, NPS 1/2 through 24.
Metal Density Chart
Steel, stainless, aluminum, brass in lb/in³, lb/ft³, g/cm³.
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