Percentage calculator

Three quick tools in one — find a percentage of a number, what percent one number is of another, and percentage change.

✓ 100% free✓ No signup✓ Instant results

What is X% of Y?

Answer

X is what percent of Y?

Answer

Percentage increase / decrease

Change
Last updated: July 2026Source: Standard percentage formulas

Percentage formulas

  • X% of Y = (X ÷ 100) × Y
  • X as a percent of Y = (X ÷ Y) × 100
  • Percent change = ((New − Old) ÷ Old) × 100

The donut chart above the first tool shows exactly what your chosen percentage looks like as a slice of the whole — a quick visual check that the number "feels right" before you use it.

Everyday uses for percentages

  • Shopping discounts — "X% of Y" tells you exactly how much you save on a sale price.
  • Restaurant tips — see our dedicated tip calculator for a faster, purpose-built version.
  • Exam scores — "X is what percent of Y" converts a raw score into a percentage grade.
  • Pay rises and price changes — the increase/decrease tool shows the exact percentage change between two numbers, e.g. how to calculate a percentage increase.

Percentages appear everywhere in daily life — discounts while shopping, tips at restaurants, tax rates, exam scores and interest rates. Bookmark this page for instant answers.

Frequently asked questions

How do I calculate X% of Y?

Multiply Y by X and divide by 100 — e.g. 15% of 200 = (15 ÷ 100) × 200 = 30.

How do I find what percent X is of Y?

Divide X by Y and multiply by 100 — e.g. 30 is 20% of 150.

How do I calculate percentage increase or decrease?

(New − Old) ÷ Old × 100. A positive result is an increase; negative is a decrease.