Percentage Calculator — Free Online % Calculator
Work out any percentage in seconds — what is X% of a number, what percent one number is of another, increase, decrease and reverse percentage. Free, exact, no sign-up.
✦ Free forever • No sign-up • Exact answers • Formulas shown
%What is X% of a number?
Find a percentage of any number — for example, a discount, a tip or a tax amount.
Example: — try it.
÷X is what % of Y?
Work out what percent one number is of another — for example, an exam score or a share of a total.
Example: — try it.
↑↓Increase / decrease by %
Add or take away a percentage — for example, a price rise, a salary increase or a sale discount.
Example: — try it.
⇄Percentage change
Find the percentage change between two numbers — a rise shows as +, a fall shows as −.
Example: — try it.
↩Reverse percentage
Find the whole when you know the part and its percentage — for example, the price before a discount.
Example: — try it.
◆Percent vs percentage points
Two percentages can differ in two ways. Try it: a rate rising from 20% to 25% is 5 percentage points — but a 25% relative increase.
Example: — try it.
How to calculate a percentage
Every calculator above shows its formula, so you can check the answer by hand. The short version: to find X% of a number, multiply the number by X and divide by 100. To find what percent one number is of another, divide the first by the second and multiply by 100. Read the full step-by-step guide with worked examples →
Why use this percentage calculator?
✓ Exact answers
Every result is calculated in your browser with exact maths, and the formula is shown so you can verify it yourself.
✓ Six calculators in one
Percent of a number, what percent, increase and decrease, percentage change, reverse percentage and percentage points.
✓ Worked examples
Each calculator has a worked example with real numbers — tap it and the answer appears, already filled in.
✓ Free forever
No account, no sign-up, no limits. Use every calculator as often as you like, on any device.
✓ Nothing is stored
Your numbers never leave your browser. Nothing is sent to any server and nothing is tracked.
✓ Works on your phone
The calculators are made for small screens too — big buttons, big numbers, no sideways scrolling.
Guides — learn percentages step by step
📖 How to Calculate a Percentage
Every formula explained with worked examples: X% of a number, what percent one number is of another, increase, decrease, reverse percentage and percentage points.
🧮 Check your answer here
Worked it out by hand? Type the same numbers into the calculators above and check your answer in seconds — each one shows its formula, so you can see exactly how it was worked out.
Calculate any percentage, free
Percentages are everywhere: sale prices, tips, tax, discounts, exam marks, salary rises and loan interest. This free percentage calculator answers all of them in seconds. Find X% of any number, work out what percent one number is of another, calculate a percentage increase or decrease, find the percentage change between two numbers, or reverse a percentage to find the whole from a part. Every answer is exact — the calculators show the formula as well as the result, so you can see how the number was worked out and check it yourself.
Everything runs in your browser and everything is free: no sign-up, no install, no upload, nothing stored. The worked examples on each calculator use real numbers you can verify by hand — 20% of 150 is 30, 45 is 30% of 150, and 150 rising to 180 is a 20% increase. If you want to understand the maths, read the free guide on how to calculate a percentage, which explains each formula with step-by-step examples, including the difference between a percent and a percentage point.
Frequently asked questions
How do I calculate a percentage of a number?
Multiply the number by the percentage and divide by 100. For example, 20% of 150 is 150 x 20 / 100 = 30. Type the numbers into the first calculator above and it does it for you.
How do I find what percent one number is of another?
Divide the first number by the second and multiply by 100. For example, 45 is 45 / 150 x 100 = 30% of 150.
How do I calculate a percentage increase?
Subtract the old number from the new number, divide by the old number and multiply by 100. For example, 150 to 180 is (180 - 150) / 150 x 100 = +20%.
What is a reverse percentage?
A reverse percentage finds the whole when you know a part and its percentage. If 30 is 20% of a number, the whole is 30 / 20 x 100 = 150.
What is the difference between percent and percentage points?
A percentage point is the simple difference between two percentages. Going from 20% to 25% is a rise of 5 percentage points, but a 25% relative increase (5 / 20 x 100).
Is this percentage calculator really free?
Yes. Percentage Calculator is 100% free. There is no account, no sign-up and no limit — use every calculator as often as you like.
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