Percentage Calculator
Percent of a number, ratios and change
100% Private & In-Browser
Processed locally using client-side JavaScript. Your files and data never touch any server.
Instant & Unlimited
No registration, no waiting queues, and no limits on file conversions or generations.
What is Percentage Calculator?
The Percentage Calculator handles the four percentage questions people actually ask: what is X% of Y, what percent is X of Y, the percentage increase from X to Y, and the percentage decrease. Every variant gets its own mode so there is no ambiguity about which number goes where.
How to use Percentage Calculator
Pick the mode matching your question (find a percentage, compare, or change over time).
Enter the two values you know.
The tool applies the matching formula instantly as you type.
Copy the result, or switch modes to check the reverse question.
- All four percentage operations in one place, mode-labeled for clarity
- Bidirectional checks — verify an increase by computing the matching decrease
- Live results with no page reloads, fully on-device
- Free with no limits for study, work, and shopping
- Working out discounts, tips, taxes, and markups without guesswork.
- Comparing this month's sales figure against last month's in percent.
- Solving homework problems and checking the reverse calculation.
Frequently Asked Questions
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