Inches to Fraction Calculator

Convert decimal inches to the nearest fraction. Select precision from 1/2 to 1/64. Essential for tape measures, woodworking, and machining.

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How to Convert Decimal Inches to Fractions

To convert a decimal inch to a fraction, multiply the decimal part by the desired denominator, round to the nearest whole number, and place over the denominator. Then reduce (simplify) the fraction.

Conversion Steps
1. Take the decimal portion (e.g., 0.625 from 3.625)
2. Multiply by denominator: 0.625 × 16 = 10
3. Write as fraction: 10/16 = 5/8
4. Result: 3-5/8"

Decimal to Fraction Reference Table

FractionDecimalmm
1/160.06251.588
1/80.12503.175
3/160.18754.763
1/40.25006.350
5/160.31257.938
3/80.37509.525
7/160.437511.113
1/20.500012.700
9/160.562514.288
5/80.625015.875
11/160.687517.463
3/40.750019.050
13/160.812520.638
7/80.875022.225
15/160.937523.813
11.000025.400

Inches to Fraction FAQ

0.375 × 8 = 3. So 0.375" = 3/8". You can also multiply by 16: 0.375 × 16 = 6, giving 6/16 = 3/8".
3/8 = 0.375 inches = 9.525 mm.
Standard tape measures mark to 1/16" (±0.031"). Machinist rulers go to 1/32" or 1/64" (±0.016" or ±0.008").