Add fractions and get the simplified answer

3/4 + 5/8 by hand means common denominators and simplifying. Enter both fractions and read the reduced answer, mixed number, and decimal.

Tools used in this guide

The job

Fraction arithmetic shows up in recipes, woodworking measurements, school work, and splitting quantities. The calculator takes two values — proper fractions, integers, or terminating decimals — applies +, −, ×, or ÷, and simplifies.

How to do it

Write each value as numerator/denominator (3/4), an integer (2), or a decimal (1.25 — which converts exactly to 5/4). The result is always reduced to lowest terms, shown as an improper fraction, a mixed number when appropriate, and a decimal.

Worked example

3/4 + 5/8: the common denominator is 8, so 6/8 + 5/8 = 11/8 = 1 3/8 = 1.375. Entered as written, the tool returns exactly that.

Limits

Arithmetic is exact integer work up to 10²⁴ — no rounding inside. Recurring decimals cannot be entered (write 1/3, not 0.333), and the decimal display marks repeating results as approximate at 12 digits.