Percentage calculator

Handle the most common percentage calculations on one page

This percentage calculator online covers three frequent use cases: finding a percent of a number, checking what percent one value is of another, and calculating percentage increase or decrease. It is useful for business math, finance checks, discounts, and everyday calculations.

Percent of a numberWhat percent is thisIncrease or decrease

Choose a percentage mode

Use the mode buttons to switch between three common percentage calculations. The result panel updates live while you change the inputs.

Percent

Number

Result

100.00

Status

25% of 400 = 100.00

Where this helps

Discount math, markup checks, dashboard analysis, GST estimates, sales changes, and basic business calculations.

Tip

Use the percentage-change mode when you want to compare old and new values instead of finding a simple ratio.