Percentage Calculator

The Percentage Calculator tool solves common percentage problems — what is X% of Y, percentage increase or decrease, and more — instantly in your browser.

Skip the mental maths and formula errors when calculating discounts, tips, tax, or changes in value. Enter your numbers and read the result immediately.

Percentage calculations turn up constantly in everyday life: working out a sale discount, calculating a tip, figuring out tax, measuring a pay rise, or tracking a change in a metric over time. Doing them in your head invites errors, especially with decimals or percentage changes, so a dedicated tool that gives an instant, exact answer is faster and more reliable than mental maths.

The tool covers the common percentage calculations in one place: what is X percent of Y, what percentage is X of Y, and the percentage increase or decrease between two values. Enter your numbers, read the result immediately, and adjust the inputs to compare different scenarios without re-entering everything.

Percentage calculation runs entirely in your browser using native JavaScript arithmetic. When you enter your values, the tool applies the standard percentage formulas — multiplying and dividing by 100 for basic percentages, and computing the difference ratio for percentage change. Results update instantly as you type, with no network request involved.

Your numbers never leave your device — there is no upload, no server-side processing, and no copy retained after you close the tab. The calculation is instant because it operates on the values in memory. Decimal values are supported for precise calculations such as tax rates and interest, so you are not limited to whole numbers.

For percentage change, enter the original and new values and the tool computes whether the change is an increase or decrease and by what percentage. For related calculations, use the Discount Calculator for sale prices, the Tip Calculator for bill splitting, and the Loan Calculator for monthly payment estimates.