Decimal inches and fractions
The result is decimal inches. For 1/4 inch, the decimal is 0.25; for 3/8 inch, it is 0.375. When choosing tools or parts, consider tolerances and specifications; similar sizes are not always interchangeable.
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Millimeters to inches.
Divide the number of millimeters by 25.4. One international inch equals exactly 25.4 mm.
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Millimeters to inches
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Millimeters to inches
How do you convert mm to inches?
Divide the number of millimeters by 25.4. One international inch equals exactly 25.4 mm. Unlike centimeters, millimeters use the divisor 25.4 rather than 2.54.
inches = millimeters ÷ 25.4 millimeters = inches × 25.4
| mm | in |
|---|---|
| 1 | 0.03937 |
| 3 | 0.11811 |
| 6 | 0.23622 |
| 10 | 0.3937 |
| 12.7 | 0.5 |
| 20 | 0.7874 |
| 25.4 | 1 |
| 50 | 1.9685 |
Example: a panel thickness of 12.7 mm
12.7 ÷ 25.4 = 0.5 inches, or half an inch. A 6 mm panel is approximately 0.23622 inches, which is not exactly a quarter inch: 1/4 inch equals 6.35 mm.
Unit relationship reference: NIST — conversion factors. Long decimal values are rounded for display.
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