13/16 Inch as a Decimal
Answer
0.8125 in
13/16 in = 0.8125 in = 20.6375 mm
13/16 inch is best known as the standard spark plug socket size found in nearly every automotive tool kit. As a decimal it equals 0.8125 inches, or 20.6375 millimeters, sitting exactly midway between 3/4 inch (0.75 in) and 7/8 inch (0.875 in). It also shows up in furniture hardware spacing and select hole saw sizes for door hardware installation.
Try another fraction
/
Decimal
0.8125
Millimeters
20.6375 mm
Related values
| Value | Result |
|---|---|
| Decimal | 0.8125 in |
| Millimeters | 20.6375 mm |
| Centimeters | 2.0638 cm |
| Feet | 0.067708 ft |
How the conversion works
- Divide. Divide the numerator (13) by the denominator (16) to convert the fraction into a decimal.
- Decimal result. 13 ÷ 16 = 0.8125. This is an exact, terminating decimal since 16 is a power of two.
- Convert to mm. Multiply the decimal by 25.4, the number of millimeters in one inch: 0.8125 × 25.4 = 20.6375 mm, useful when matching a metric drawing or socket to an imperial part.
Frequently Asked Questions
13/16 equals 0.8125 as a decimal. Divide the numerator, 13, by the denominator, 16, to get this result. It is a fine gradation between 3/4 inch and 7/8 inch on a tape measure or machinist rule.
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0.8125 as a Fraction
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