1/2 Inch as a Decimal
Answer
0.5 in
1/2 in = 0.5 in = 12.7 mm
1/2 inch is the biggest fractional mark between two whole inches on a tape measure, sitting exactly at the midpoint. As a decimal it equals 0.5 inches, or 12.7 millimeters. It is best known as the drive size on half-inch drive ratchets and impact wrenches used in automotive and construction work, and it is also a common plywood, rebar, and threaded rod diameter, falling exactly between 7/16 inch (0.4375 in) and 9/16 inch (0.5625 in).
Try another fraction
/
Decimal
0.5
Millimeters
12.7 mm
Related values
| Value | Result |
|---|---|
| Decimal | 0.5 in |
| Millimeters | 12.7 mm |
| Centimeters | 1.27 cm |
| Feet | 0.041667 ft |
How the conversion works
- Divide. Divide the numerator (1) by the denominator (2) to convert the fraction directly into a decimal.
- Decimal result. 1 ÷ 2 = 0.5. This is an exact, terminating decimal since 2 divides evenly into 10.
- Convert to mm. Multiply the decimal by 25.4, the fixed number of millimeters in one inch: 0.5 × 25.4 = 12.7 mm, useful for matching a metric drawing or bolt to an imperial part.
Frequently Asked Questions
1/2 equals 0.5 as a decimal. Divide the numerator, 1, by the denominator, 2, to get this result. It is the largest fractional mark on a standard tape measure, sitting exactly halfway between two whole-inch lines.
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