Percent Calculator – Calculate Percentages Online
Solve all common percentage problems: percent of, is what percent, and percent change.
About the Percentage Calculator
What is the Percentage Calculator?
A percentage calculator handles the three percentage questions that come up constantly: finding a percent of a number, expressing one number as a percent of another, and calculating percent change.
Why use this calculator?
Percentages are used in finance, shopping, statistics and everyday life. Getting them right avoids costly errors in pricing, tips and comparisons.
How to use it
- Choose the type of percentage problem.
- Enter the two values.
- Read the result instantly.
Formula
Percent of: X% × Y. Is what percent: X ÷ Y × 100. Change: (Y − X) ÷ |X| × 100.
Percent change uses the absolute value of the starting number so the direction of change reads correctly.
Frequently Asked Questions
How do I calculate a tip percentage?
Multiply the bill by the tip rate. For 20% on a $50 bill, compute 50 × 0.20 = $10.
What is the difference between percent change and percentage points?
Percent change is relative; percentage points are absolute. Going from 4% to 6% is a 2 percentage-point rise but a 50% increase.
What order of operations does this use?
It follows standard PEMDAS/BODMAS rules: parentheses, exponents, multiplication and division, then addition and subtraction.
How precise are the answers?
The calculator uses double-precision floating-point math (about 15 significant digits) and rounds the display. For exact symbolic results use dedicated algebra software.
Can I enter negative numbers or decimals?
Yes. Negative values, decimals and very large or small numbers are all supported unless a field says otherwise.
What does it mean if I get an error?
Errors usually mean an invalid input, such as division by zero or a negative value where only positives make sense. Check your entries and try again.
Is this calculator free to use?
Yes. Every calculator on this site is completely free, with no hidden fees, no subscriptions and no limits on how many times you can use it.
How accurate are the results?
We use standard, widely accepted formulas and calculate in your browser using double-precision arithmetic. Results are rounded for readability, so treat them as reliable estimates rather than a guarantee. Real-world factors can vary the true figure.
Can I add this calculator to my own website?
Yes. Open this calculator page and use the "Add to your website" box in the sidebar to copy a ready-made iframe snippet, then paste it into any HTML page.
Does it work on a phone or tablet?
Yes. The layout is fully responsive, so it works on desktops, laptops, tablets and mobile phones, and every input adapts to touch screens.