Fraction to Decimal Converter

Turn one fraction into a decimal and a percent — homework checks and “what is 3/8 as a decimal,” not adding two fractions together.

How to use

Enter the numerator (top) and denominator (bottom).
Read the decimal and the same value as a percentage.
Improper fractions are fine: 5/4 is 1.25 and 125%.
Use the fraction calculator if you need to add, subtract, multiply or divide two fractions.

How it works

A fraction is already a division. 1/4 is 1 ÷ 4 = 0.25, which is 25%. 3/8 is 0.375 and 37.5%. 2/5 is 0.4 and 40%. Those terminating decimals match the usual school table.

Repeating decimals are rounded to the display precision. 1/3 is 0.333333…, shown as 0.333333 at six places, not a vinculum. 2/3 is 0.666667 after ordinary rounding. Do not treat the last digit as exact if you need a proof that 1/3 ≠ 0.333333 exactly.

Improper fractions are larger than one: 3/2 = 1.5 = 150%. Negative numerators give a negative decimal. A zero denominator is undefined and is rejected.

This is not a ratio simplifier. 8/12 as a decimal is 0.666…; as a ratio it reduces to 2:3. Use the ratio page for lowest terms of a pair you want to keep as A:B.

It is also not the percentage calculator’s “X is what percent of Y” mode, though 3 of 8 is the same 37.5% if you treat 8 as the whole.

A mixed number such as 1 3/4 is 7/4 = 1.75. Convert the mixed form to an improper fraction first; this page has no whole-plus-fraction field. Rounding a repeating decimal back to a fraction is not offered — keep 1/3 if you need the exact value.

Formula

Decimal = numerator ÷ denominator
Percentage = decimal × 100

Worked examples

A quarter
1 / 4 → 0.25, 25%
An improper fraction
3 / 2 → 1.5, 150%

School fractions that terminate

Fraction	Decimal	Percent
1/2	0.5	50%
1/4	0.25	25%
3/4	0.75	75%
1/5	0.2	20%
3/8	0.375	37.5%
5/8	0.625	62.5%

Useful notes

Repeating decimals are rounded, not written with a bar.
Zero denominator is rejected.
One fraction only — arithmetic of two fractions is the other page.

FAQ

How do I convert a fraction to a decimal?: Divide the numerator by the denominator. 1 ÷ 4 = 0.25.
How do I convert a fraction to a percent?: Convert to a decimal first, then multiply by 100. 1/4 = 0.25 = 25%.
What if the denominator is zero?: The value is undefined. The tool does not print Infinity or NaN.
What is 5/8 as a decimal and a percent?: 0.625 and 62.5%.
Why isn’t 1/3 shown as 0.3 repeating?: The display is a rounded floating-point value. For exact work keep the fraction 1/3.

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