Percentage Calculator
Calculate percentages, percentage increases and decreases, and what percentage one number is of another.
What is X% of Y?
X is what % of Y?
Percentage Change
ℹ️ About Percentage Calculator
Use these three common percentage formulas for discounts, price changes, grades, business calculations, statistics, tips and everyday math. Calculations happen locally in your browser.
🛠️ How to Use Percentage Calculator
Choose the calculation you need, enter the numbers, and click Calculate. The result appears instantly without sending your numbers to a server.
📥 Input → ⚙️ Process → 📤 Result
Input
Percentages or numeric values.
Process
Applies the appropriate percentage formula in JavaScript.
Result
Instant percentage result.
❓ Frequently Asked Questions
How do I calculate a percentage of a number?
Enter the percentage and number in the first calculator.
How do I calculate percentage increase?
Use the Percentage Change calculator with the original and new values.
Are my numbers uploaded?
No. Calculations are performed locally in your browser.
Practical ways to use Percentage Calculator
Small text and data utilities like this one get used constantly by developers, students and anyone doing quick calculations or formatting — often several times in a single work session. The three calculators here cover the most common percentage questions separately: finding a percentage of a number, finding what percent one number is of another, and calculating percentage change. Everything above runs locally in your browser tab — the file you choose is not uploaded to a ToolBoxly server before you download the result, so there is nothing to wait on beyond your own device's processing speed. If you plan to use the result somewhere else — a client deliverable, an app store listing, a printed page — keep a copy of your original file and double-check the output against that destination's specific requirements before you rely on it.