Fraction to decimal converter

Type a fraction, a mixed number like 3 5/8, or a whole calculation such as (3/8)+(1/16) — the decimal updates as you type, to 10 significant digits. Built for woodworking, machining, construction take-offs and homework alike.

Decimal
3.625
improper: 29/8nearest 1/16: 3 5/8nearest 1/32: 3 5/8
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Worked examples

5/8

5 ÷ 8

0.625

3 5/8

3 + (5 ÷ 8)

3.625

7/16

7 ÷ 16

0.4375

Common fractions

1/20.5
1/30.33333333
2/30.66666667
1/40.25
3/40.75
1/50.2
2/50.4
3/50.6
4/50.8
1/60.16666667
5/60.83333333
1/80.125
3/80.375
5/80.625
7/80.875
1/160.0625
3/160.1875
5/160.3125
7/160.4375
9/160.5625
11/160.6875
13/160.8125
15/160.9375
1/320.03125

Inch fractions — decimal & mm

1/64"0.0156250.39687 mm
1/32"0.031250.79375 mm
3/64"0.0468751.1906 mm
1/16"0.06251.5875 mm
5/64"0.0781251.9844 mm
3/32"0.093752.3812 mm
7/64"0.1093752.7781 mm
1/8"0.1253.175 mm
9/64"0.1406253.5719 mm
5/32"0.156253.9688 mm
11/64"0.1718754.3656 mm
3/16"0.18754.7625 mm
13/64"0.2031255.1594 mm
7/32"0.218755.5562 mm
15/64"0.2343755.9531 mm
1/4"0.256.35 mm
5/16"0.31257.9375 mm
3/8"0.3759.525 mm
7/16"0.437511.112 mm
1/2"0.512.7 mm
9/16"0.562514.287 mm
5/8"0.62515.875 mm
11/16"0.687517.462 mm
3/4"0.7519.05 mm
13/16"0.812520.637 mm
7/8"0.87522.225 mm
15/16"0.937523.813 mm
1/1"125.4 mm

The formula

decimal = numerator ÷ denominator

mixed number: decimal = whole + (numerator ÷ denominator)

Repeating results (1/3, 1/6, 1/7…) are shown to 10 significant digits, which is more than enough for any shop tolerance.

Questions

How do you convert a fraction to a decimal?

Divide the numerator by the denominator. For 5/8, 5 ÷ 8 = 0.625. For a mixed number like 3 5/8, keep the whole number and add the divided part: 3 + 0.625 = 3.625.

What is 5/8 as a decimal?

5/8 = 0.625 exactly. In sixteenths it is 10/16, and in thirty-seconds 20/32.

Why do some fractions never end?

A fraction terminates only when the denominator's prime factors are 2 and 5. 1/3 = 0.333… and 1/6 = 0.1666… repeat forever, so this page shows them to 10 significant digits.

Can I type a calculation instead of a single fraction?

Yes. The box runs a live math parser, so (3/8)+(1/16), 2*7/16 and 3 5/8 - 1/4 all give an answer as you type.

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