Gauge to MM Converter | Stainless Steel Sheet Gauge Chart
This gauge to mm converter helps buyers and fabricators convert common stainless steel sheet gauge values into millimeters and inches. Gauge references can vary by material and standard, so use this page as a purchasing reference and confirm final thickness on the drawing or purchase order.
Gauge to mm converter
Reference: New Source Corporation stainless steel gauge chart, page 2. Conversion: NIST, 1 inch = 25.4 mm exactly. Gauge tables are material-specific nominal references; confirm the contractual thickness and tolerance. The mm column is recalculated from the source inch values, so it can differ from the source’s truncated mm column. Table and conversions checked on 2026-09-04.
Use the stainless steel gauge table below when JavaScript is unavailable.
Formula
Inches = millimeters / 25.4. Gauge itself is a reference table rather than a linear formula, so always confirm the required millimeter thickness on the purchase order.
Common stainless steel gauge chart
| Gauge | Millimeters | Inches |
|---|---|---|
| 10 | 3.5717 | 0.14062 |
| 12 | 2.7780 | 0.10937 |
| 14 | 1.9842 | 0.07812 |
| 16 | 1.5875 | 0.06250 |
| 18 | 1.2700 | 0.05000 |
| 20 | 0.9525 | 0.03750 |
| 22 | 0.7937 | 0.03125 |
| 24 | 0.6350 | 0.02500 |
| 26 | 0.4762 | 0.01875 |
Buying notes
- For international orders, specify thickness in millimeters instead of only gauge.
- Confirm tolerance, surface finish, grade, and sheet or coil form.
- Use the weight calculators after converting gauge to mm.
How to use gauge in purchasing
Gauge is convenient in conversation, but millimeters are clearer for international stainless steel purchasing. A buyer may say 16 gauge, while the drawing, mill tolerance, and supplier stock list may use millimeter thickness. To avoid mistakes, convert the gauge to millimeters and write the millimeter value directly into the inquiry or purchase order.
For stainless steel sheet and coil, the thickness affects weight, price, forming behavior, stiffness, and freight cost. After converting gauge to millimeters, use the sheet or coil weight calculator to estimate total material weight. This makes it easier to compare options such as 18 gauge versus 16 gauge before requesting a quote.
Common buying mistakes
- Ordering by gauge only without confirming millimeter thickness.
- Assuming gauge tables are identical for stainless steel, carbon steel, and aluminum.
- Forgetting to check thickness tolerance and surface finish.
- Using gauge for quotation but millimeters for inspection without aligning both values.
Best practice for buyers
Use gauge as a quick reference, then confirm the exact millimeter thickness, tolerance, grade, finish, sheet or coil form, and quantity. For export orders, millimeters reduce ambiguity between buyer, supplier, freight forwarder, and inspection team.
Related pages
Final buyer note
For formal purchasing, include this calculated estimate in the inquiry but ask the supplier to confirm theoretical weight, actual production weight, packing weight, and gross shipment weight. This gives purchasing, warehouse, and freight teams the same basis for cost planning.
Final buyer note
Always confirm the exact millimeter thickness before payment or production.
Request a quote
Use the converted thickness as a reference, then send the exact material type, grade, size, quantity, surface finish, application, and destination country for a formal quotation.
FAQ
Is gauge the same for every metal?
No. Gauge values vary by material and standard, so confirm the millimeter thickness for stainless steel.
Should I order by gauge or millimeters?
For clear purchasing, specify millimeters and tolerance on the purchase order.