Fraction to Decimal Calculator

Enter any numerator and denominator to convert the fraction to a decimal and a percentage — division done exactly, with the method shown.

The one-step method

Every fraction is a division in disguise: the top divided by the bottom. That is the entire conversion — 3/8 means 3 ÷ 8 — and this calculator does it exactly, shows the percentage alongside, and a two-decimal rounding for everyday use. It also refuses politely when the denominator is zero, because that division has no answer.

How to use it

  1. Enter the numerator (top number).
  2. Enter the denominator (bottom number).
  3. Read the decimal, the percentage, and the rounded form.

The rule

decimal = numerator ÷ denominator · percent = decimal × 100

A worked example

3/8 = 3 ÷ 8 = 0.375, which is 37.5%. Some fractions terminate like that; others repeat forever — 1/3 is 0.333… and 1/7 is 0.142857 recurring — which is why the calculator shows plenty of digits and the rounded version side by side. Mixed numbers convert too: 2¾ is (2×4+3)/4 = 11/4 = 2.75. Negative fractions carry their sign straight through the division: −3/8 is simply −0.375, and the percentage keeps the sign as well.

Common questions

Why do some fractions repeat forever?
A fraction terminates only when its simplified denominator’s prime factors are just 2s and 5s — the factors of 10. Anything else (3, 7, 11…) produces a repeating decimal.
How do I convert a mixed number?
Turn it improper first: whole × denominator + numerator over the same denominator. 2¾ → 11/4 → 2.75.
How do I go back from a decimal to a fraction?
Put the digits over their place value and simplify: 0.375 = 375/1000 = 3/8. The fraction calculator on this site handles the arithmetic.