Percentage Calculator
What is X% of a number, what percent one value is of another, the rise or fall between two figures, and sale prices after a discount — all on one page.
Every calculation happens in your browser — the numbers you type never leave your device.
FAQ
How is the percentage change worked out?
The difference between the new and old value is divided by the old value: (new − old) ÷ old × 100. A positive result is a rise, a negative one a fall. Going from 200 to 250 is +25%, while 250 back to 200 is −20% — the base changes, so the two directions aren’t symmetric.
How do I work out a sale price?
Pick the Discount mode, enter the original price and the percent off. You’ll see what you pay and what you keep in your pocket — 20% off an $80 item leaves $64 to pay and $16 saved.
Why doesn’t +10% followed by −10% get back to the start?
Each step is measured against a different base. Adding 10% to 100 gives 110, but 10% of 110 is 11, so subtracting it lands at 99 — not 100. The larger the percentage, the wider that gap becomes.