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Percentage Calculator
Four modes: what is X% of Y, X plus/minus X%, percentage change from X to Y, and X is what % of Y. Shows formula and steps. Runs locally.
100% Private & Secure
This tool runs in your browser.
Your data is never uploaded or stored.
What is X% of Y?
Enter values below and click Calculate.
How to use
- 1
Choose a calculation mode.
- 2
Enter the values.
- 3
See the result with the formula.
Why use this tool?
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Fast, instant results — no waiting, no page reloads.
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Clean, focused interface designed for developers.
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100% private — everything runs in your browser, nothing is uploaded to any server.
Frequently Asked Questions
What calculation modes are available?
Percentage of a number, add/subtract percentage, percentage change, and percentage of total.
Does it show the formula?
Yes. Each result includes the formula used.