Fractional Inches to Millimetre Conversions

Inches to millimetre conversion table:

(With decimal equivalents)

The metals industry can be rather confusing when sourcing items from international suppliers. American suppliers still use gauges and inches when referring to metal thicknesses. For more information on gauges see our article on the differences between sheet, plate and coil. For simple conversions use the table below.

 

InchInch/DecimalmmInchInch/Decimalmm
1/64″.015620.39733/64″.5156213.097
1/32″.03120.79417/32″.5312513.494
3/64″.046871.19135/64″.5468713.891
1/16″.06251.5889/16″.562514.287
5/64″.078121.98437/64″.5781214.684
3/32″.09372.38119/32″.5937515.081
7/64″.109372.77839/64″.6093715.478
1/8″.1253.1755/8″.62515.875
9/64″.140623.57241/64″.6406216.272
5/32″.15623.96921/32″.6562516.669
11/64″.171874.36643/64″.6718717.066
3/16″.18754.76311/16″.687517.462
13/64″.203125.15945/64″.7031217.859
7/32″.218755.55623/32″.7187518.256
15/64″.234375.95347/64″.7343718.653
1/4″.256.3503/4″.7519.050
17/64″.265626.74749/64″.7656219.447
9/32″.281257.14425/32″.7812519.844
19/64″.296877.54151/64″.7968720.241
5/16″.31257.93713/16″.812520.637
21/64″.328128.33453/64″.8281221.034
11/32″.343758.73127/32″.8437521.431
23/64″.359379.12855/64″.8593721.828
3/8″.3759.5257/8″.87522.225
25/64″.390629.92257/64″.8906222.622
13/32″.4062510.31929/32″.9062523.019
27/64″.4218710.71659/64″.9218723.416
7/16″.437511.11215/16″.937523.812
29/64″.4531211.50961/64″.9531224.209
15/32″.4687511.90631/32″.9687524.606
31/64″.4843712.30363/64″.9843725.003
1/2″.512.7001″1.025.400