What can I calculate with this tool?

Enter two values (A and B) to instantly get five results: A% of B, what percentage A is of B, the percentage change from A to B, B increased by A%, and B decreased by A%.

How do I calculate percentage change?

Enter the original value as A and the new value as B. The '% Change A→B' row shows the percentage increase or decrease. A positive result means an increase; a negative result means a decrease.

Is the percentage calculator free?

Yes, completely free. All calculations run entirely in your browser — no data is sent to any server, and no signup is required.

Percentage Calculator

Calculate percentages instantly online. Find X% of Y, what % one number is of another, percentage change, and more — all in one tool. Free, no signup, runs entirely in your browser.

Examples:

Value A

and

Value B

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How to Use the Percentage Calculator

Enter any two numbers in the Value A and Value B fields.
All five percentage calculations update instantly.
Use the example presets to quickly load common scenarios.
Click "Copy" next to any result to copy the value.

What Each Calculation Means

A% of B — e.g., 25% of 200 = 50
A is ?% of B — e.g., 50 is 25% of 200
% Change A→B — e.g., from 100 to 150 = +50% increase
B + A% — e.g., 200 increased by 25% = 250
B − A% — e.g., 200 decreased by 25% = 150