← Back to all calculators

Math

Percentage Calculator

Find percentages of numbers, calculate percentage change, and work out what percentage one value is of another.

Percentage Calculator Guide

What is the Percentage Calculator?

The Percentage Calculator solves three of the most common percentage problems instantly. Whether you need to find a percentage of a number, calculate the percentage change between two values, or determine what percentage one number is of another, this tool has you covered.

How to calculate it manually

% of number: (percentage ÷ 100) × number. % change: ((new − old) ÷ |old|) × 100. X is what % of Y: (X ÷ Y) × 100.

Frequently Asked Questions

Multiply 240 by 0.15 (which is 15 ÷ 100). 240 × 0.15 = 36. So 15% of 240 is 36.

Subtract the old value from the new value, divide by the old value, and multiply by 100. Going from £80 to £100 is a 25% increase: (100−80)/80 × 100 = 25%.

Finding the original value before a percentage change was applied. If a price is £120 after a 20% increase, the original was £120 ÷ 1.20 = £100.

Multiply the original price by the discount rate: £80 × 0.25 = £20 saving. Subtract to get the final price: £80 − £20 = £60.