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Decimal to Fraction

Convert a decimal to an exact fraction in lowest terms, including repeating decimals.

Maximum denominator

Exact keeps the true fraction, however large. Picking a denominator snaps the result to the closest common fraction, useful for measurements.

Repeating decimals are recognized as 0.333... or 0.1(6), and convert to an exact fraction rather than a rounded one.

Result

Fraction
3/4
Mixed number3/4
Decimal value0.75

How to convert a decimal to a fraction

  1. Type the decimal

    Enter a decimal like 0.75, or a repeating decimal written as 0.333... or 0.1(6).

  2. Choose a maximum denominator

    Leave Exact selected for the true fraction, or pick a denominator like sixteenths to snap the result to a common measurement.

  3. Read the fraction

    The fraction in lowest terms appears instantly, along with its mixed number and decimal forms.

Why use this tool

Exact repeating decimals

Decimals written as 0.333... or 0.1(6) are converted to their exact fraction, not a rounded approximation.

Always in lowest terms

The numerator and denominator are reduced by their common factor automatically, so the answer never needs simplifying by hand.

Mixed number form

Decimals greater than one also show the whole-number-plus-fraction form alongside the improper fraction.

Snap to common denominators

Cap the denominator at halves, quarters, eighths, sixteenths, and more so results read as familiar measurement fractions.

Honest about approximations

When a capped denominator cannot represent the decimal exactly, the difference from the true value is shown alongside the result.

Runs entirely in your browser

Every conversion happens on your device as you type. Nothing is uploaded or stored.

About this tool

Every terminating or repeating decimal is also a fraction, and this tool finds that fraction directly rather than guessing from a rounded decimal. A terminating decimal like 0.75 converts by reading its digits as a whole number over the matching power of ten, then reducing. A repeating decimal, written either as 0.333... or with the shorter 0.1(6) notation, converts using the same algebraic trick used to prove such decimals are rational: the exact fraction comes out whole, with no rounding involved.

The result always appears reduced to lowest terms, alongside its mixed number form for values greater than one, so a fraction like 11/4 also shows as 2 3/4. This matters for anything read off a ruler, a recipe, or a cutting list, where the mixed form is usually the one that gets written down or spoken aloud.

Real measurements are not always exact, though, which is what the maximum denominator setting is for. Woodworking and machining tend to work in sixteenths or thirty-seconds of an inch, so capping the denominator snaps an odd decimal like 0.3 to the closest sixteenth instead of an unusable exact fraction, and shows how far off that snap is from the true value. For other unit conversions, see the full unit converter, convert measurements across number bases with the number base converter, or work through a recipe’s fractional amounts with the cooking converter.

Frequently asked questions

How do repeating decimals like 0.333... convert exactly?
The tool recognizes the trailing dots or a parenthesis notation like 0.1(6) as marking a repeating block, then uses the algebraic method for repeating decimals to compute the exact fraction, rather than rounding the decimal first.
What formats can I use for a repeating decimal?
Either 0.333... with at least two repeats of the digit shown before the dots, or the more precise 0.1(6) form, where the digits in parentheses are the ones that repeat.
What does the maximum denominator setting do?
It caps the result to a denominator like 16 or 32, which snaps the decimal to the closest fraction with that denominator. This is useful for measurements read from a ruler or tape measure, where exact fractions are not practical.
How do I know if the result is exact or approximate?
When a maximum denominator forces rounding, a note beneath the fraction shows how far the snapped value is from the true decimal. Exact mode never shows this note, since the fraction always matches precisely.
Is my number uploaded anywhere?
No. Every conversion runs in your browser, and nothing is sent to a server or stored.

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