Why use PercentCalc?
- 100% free, no signup. Open the page and use the tool — no account, no email, no paywall.
- Private by design. Everything runs in your browser. Your inputs never leave your device.
- Fast on any device. Lightweight pages that load instantly on mobile and desktop.
Guides & how-tos
Practical guides about percentage calculators — written to actually help, not to waste your time.
📖
How to Calculate a Percentage (3 Formulas You'll Actually Use)
Percentages show up in discounts, taxes, grades, tips and interest — and almost every percentage problem is one of three formulas.
📖
Percentage Increase vs Percentage Points: The Difference Matters
News headlines mix these up constantly — and the difference can make a small change sound huge (or the reverse).
Frequently asked questions
How do I find 20% of 150?
Use mode 1: enter 20 and 150. The answer is 30.
How do I find the percentage increase?
Use mode 3: enter the old value and the new value. A result of +25% means the value grew by a quarter.
What is the formula?
Percentage = (part ÷ whole) × 100. This tool applies it for you in all three directions.