Percentage Calculator
Calculate percentages, changes, and markups.
- 100% free
- Private in browser
- No signup
- No watermarks
Result
10% of 200
20
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About Percentage Calculator
Quick percent math without a spreadsheet. Percentage Calculator on TheToolss covers the five questions that actually come up: what is X% of Y, X is what percent of Y, percent change between two numbers, and increasing or decreasing a value by a percent. Percent change is the one worth having a tool for, since the direction of the base value decides the answer and reversing it gives a different result. Handy for discounts, tips, margins, grades, and salary changes. Results update as you type — free, private, and mobile-friendly.
How to use Percentage Calculator
- Pick a calculation mode.
- Enter the two numbers.
- Read the result instantly.
Key features
- Five common percentage modes
- Percent of and reverse percent
- Percent change between values
- Increase or decrease by %
- Private browser calculation
Frequently asked questions
- Is Percentage Calculator free?
- Yes. Use Percentage Calculator free on TheToolss — no signup required.
- Is my data uploaded?
- No. Processing runs locally in your browser whenever possible.
- Can I use it on mobile?
- Yes. Open the tool in a mobile browser.
- Do I need an account?
- No account is required.
- Does it work privately?
- Yes. Client tools keep your inputs on-device.