15% of 200 = 30. Use the 'X% of Y' mode, enter 15 and 200.

How do I calculate percentage change?

Use the '% change' mode. Enter the starting value and ending value. The formula is ((end - start) / |start|) × 100.

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

Use the 'X is what % of Y' mode. For example, 30 is 15% of 200.

Calculate percentages three ways: X% of Y, what percent X is of Y, and percent change. Instant results in your browser.

1
Choose a calculation type
Select one of three modes: percentage of a number, what percent is X of Y, or percentage change.
2
Enter your values
Fill in the two input fields with the numbers you want to work with.
3
Read the result
The answer updates instantly as you type.

What is 15% of 200?: 15% of 200 = 30. Use the 'X% of Y' mode, enter 15 and 200.
How do I calculate percentage change?: Use the '% change' mode. Enter the starting value and ending value. The formula is ((end - start) / |start|) × 100.
How do I find what percentage one number is of another?: Use the 'X is what % of Y' mode. For example, 30 is 15% of 200.

Add, subtract, multiply, or divide two fractions. Results are automatically simplified and shown as a fraction and decimal.

Convert Celsius to Fahrenheit or Fahrenheit to Celsius instantly in your browser. Bidirectional live conversion.

Convert kilometres to miles or miles to kilometres instantly. Bidirectional live conversion in your browser.

Format, validate, and minify JSON instantly in your browser. Your data never leaves your device.

Decode JWT tokens and inspect header and payload instantly in your browser. Your tokens never leave your device.

Count words, characters, sentences, and estimate reading time instantly in your browser. No sign-up required.