Percentage Calculator

Calculate percentages instantly with three modes. Find what X% of a number is, figure out what percentage one value is of another, or compute the percentage change between two numbers. Results update live as you type.

Result
50
25% x 200 = 50
Quick reference

Results update live as you type. Percentage change handles negative starting values correctly using the absolute value.

How it works

The calculator supports three common percentage operations. "X% of Y" multiplies the percentage by the number (e.g., 25% of 200 = 50). "X is what % of Y" divides the first number by the second and multiplies by 100 to find the ratio. "% Change" computes how much a value increased or decreased relative to the original, using the absolute value of the starting number.

All calculations happen in your browser with no rounding until the final display. The formula is shown alongside every result so you can verify the math or use it in your own work.

The quick-reference buttons below the result let you instantly see common percentages of whatever number you have entered, which is handy for discounts, tips, or tax estimates.