How do I calculate a percentage of a number?

Divide the percentage by 100 and multiply by the number. So 15% of 200 is 0.15 × 200 = 30. The calculator does this in the first mode: type the percent and the number and read the answer.

How do I find what percent one number is of another?

Divide the first number by the second and multiply by 100. So 30 out of 120 is 30 ÷ 120 × 100 = 25%. Use the second mode and enter the part and the whole.

How do I calculate percentage increase or decrease?

Subtract the old value from the new value, divide by the old value, then multiply by 100. Going from 50 to 75 is (75 − 50) ÷ 50 × 100 = 50%. A positive result is an increase and a negative one is a decrease. Use the third mode.

Does this work offline and is anything sent to a server?

The calculation runs entirely in your browser, so nothing you type is sent anywhere, and once the page has loaded it keeps working with no connection. There is no sign-up and no limit on how many calculations you make.

Percentage Calculator

Work out percentages three ways: find X% of a number, find what percent one number is of another, and find the percent increase or decrease between two values. Type the numbers and read the answer instantly, with the method shown. Free, in your browser.

Exact, step-by-step answers
100% free
No sign-up, no app
Instant as you type
Works offline after first load

Read the guide: How to Calculate a Percentage

Percent (%)of value

15% of 200

15% × 200 = 15 ÷ 100 × 200 = 30

How to use it

1
Choose a mode

Pick the question you are answering: percent of a number, what percent, or percent change.
2
Enter your numbers

Fill in the two values for that mode. The result updates as you type.
3
Read the answer

See the result with the calculation behind it, so the number makes sense rather than appearing from nowhere.

When it comes in handy

Discounts and sales

Find the saving on a marked-down price, or what percent you saved compared with the original.

Tips and tax

Add a percentage tip or tax to a bill, or check what percent a charge is of the total.

Results and change

Turn a score into a percentage, or measure how much a figure rose or fell between two points.

Instant, exact & 100% in your browser

The maths runs right here in your browser, with fractions and whole numbers kept exact rather than rounded along the way. Nothing you type is sent to a server, there is no sign-up and no limit, and once the page has loaded it keeps working even with no connection.

Frequently asked questions

How do I calculate a percentage of a number?: Divide the percentage by 100 and multiply by the number. So 15% of 200 is 0.15 × 200 = 30. The calculator does this in the first mode: type the percent and the number and read the answer.
How do I find what percent one number is of another?: Divide the first number by the second and multiply by 100. So 30 out of 120 is 30 ÷ 120 × 100 = 25%. Use the second mode and enter the part and the whole.
How do I calculate percentage increase or decrease?: Subtract the old value from the new value, divide by the old value, then multiply by 100. Going from 50 to 75 is (75 − 50) ÷ 50 × 100 = 50%. A positive result is an increase and a negative one is a decrease. Use the third mode.
Does this work offline and is anything sent to a server?: The calculation runs entirely in your browser, so nothing you type is sent anywhere, and once the page has loaded it keeps working with no connection. There is no sign-up and no limit on how many calculations you make.