About Percentage Calculator
Solve everyday percentage problems: what is X% of Y, what percent one number is of another, and percentage increase or decrease between two values — all in one place.
How to Use
- Pick the type of percentage calculation you need.
- Enter your two numbers.
- Read the result instantly.
- Use the increase/decrease mode to compare an old and new value.
Why Use This Tool?
- Accurate — built on precise, well-tested mathematical formulas.
- Instant — all calculations happen client-side for zero latency.
- Private — no data is sent to any server; your information stays on your device.
- Free — no sign-up, no limits, no hidden costs.
Frequently Asked Questions
How do I calculate what percent one number is of another?
Divide the part by the whole and multiply by 100. For example, 45 out of 60 is (45 ÷ 60) × 100 = 75%.
How do I calculate percentage increase?
Percentage change = ((new − old) ÷ old) × 100. Going from 80 to 100 is ((100 − 80) ÷ 80) × 100 = 25% increase; a negative result means a decrease.
How do I find X% of a number?
Multiply the number by the percentage divided by 100. For example, 18% of 250 is 250 × 0.18 = 45.