Decimal to fraction converter

Type any decimal — or a calculation like 12.5/4 — and get the exact simplified fraction, plus the nearest 1/16 and 1/32 with the rounding error, so you always know which mark to cut to.

Fraction
3/8
improper: 3/8nearest 1/16: 3/8nearest 1/32: 3/8
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Worked examples

0.375

375/1000 ÷ 125

3/8

2.4375

2 + 4375/10000

2 7/16

0.333333

closest simple ratio

1/3

Common decimals

0.06251/16
0.11/10
0.1251/8
0.1666671/6
0.21/5
0.251/4
0.33/10
0.3333331/3
0.3753/8
0.42/5
0.51/2
0.63/5
0.6255/8
0.6666672/3
0.77/10
0.753/4
0.84/5
0.8333335/6
0.8757/8
0.99/10
1.251 1/4
1.51 1/2
1.751 3/4
2.52 1/2

Decimal inch → nearest 64th & mm

0.0156251/64"0.39687 mm
0.031251/32"0.79375 mm
0.0468753/64"1.1906 mm
0.06251/16"1.5875 mm
0.0781255/64"1.9844 mm
0.093753/32"2.3812 mm
0.1093757/64"2.7781 mm
0.1251/8"3.175 mm
0.1406259/64"3.5719 mm
0.156255/32"3.9688 mm
0.17187511/64"4.3656 mm
0.18753/16"4.7625 mm
0.20312513/64"5.1594 mm
0.218757/32"5.5562 mm
0.23437515/64"5.9531 mm
0.251/4"6.35 mm
0.26562517/64"6.7469 mm
0.281259/32"7.1437 mm
0.29687519/64"7.5406 mm
0.31255/16"7.9375 mm
0.32812521/64"8.3344 mm
0.3437511/32"8.7312 mm
0.35937523/64"9.1281 mm
0.3753/8"9.525 mm
0.39062525/64"9.9219 mm
0.4062513/32"10.319 mm
0.42187527/64"10.716 mm
0.43757/16"11.112 mm
0.45312529/64"11.509 mm
0.4687515/32"11.906 mm
0.48437531/64"12.303 mm
0.51/2"12.7 mm

The method

fraction = decimal × 10ⁿ / 10ⁿ, then simplify

For repeating or untidy decimals the converter searches for the simplest fraction that matches your value, then also rounds it to the nearest 1/16, 1/32 and 1/64 — the marks that exist on a real tape measure.

Questions

How do you convert a decimal to a fraction?

Write the decimal over its place value, then simplify. 0.375 = 375/1000, and dividing both by 125 gives 3/8. This page does that automatically and also reduces the result.

What is 0.375 as a fraction?

0.375 = 3/8 exactly. In sixteenths it is 6/16, and in sixty-fourths 24/64.

Why do I get a nearest 1/16 instead of an exact fraction?

Decimals like 0.1 or 2.37 have no tidy fraction on a tape measure. The exact fraction is shown first, and the nearest 1/16, 1/32 and 1/64 are given with the rounding error so you can pick a mark you can actually cut to.

Does it handle repeating decimals?

Yes. 0.333333 resolves to 1/3 and 0.166666667 to 1/6, because the converter looks for the simplest fraction that matches the value you typed.

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