Work out percentages six ways: a percent of a value, what percent one number is of another, the base behind a percent, percentage change, increase or decrease, and percentage difference.
How to use the Percentage Calculator
Pick the type of calculation you need from the dropdown.
Enter the two values. The labels change to match the chosen calculation.
Read the result and the plain-language explanation below it.
The percentage calculator covers the calculations people reach for most often, in one place: finding a percentage of a value, expressing one number as a percentage of another, finding the base value behind a percentage, percentage increase and decrease, and the percentage change or difference between two numbers.
Percentages are just fractions of 100, but the everyday questions take different forms, and it is easy to mix them up. Having each as its own mode means you pick the question you actually have rather than rearranging a formula by hand.
Each mode shows a clear result plus a short sentence that spells out the calculation, so you can check the logic at a glance and trust the answer.
It is handy across daily life: discounts and sale prices, tips, taxes and VAT, interest, grades, statistics, and any quick share-of-a-total question.
A couple of the trickier ones are worth knowing. To remove a percentage already included in a price, you divide rather than subtract, since adding 20 percent and removing 20 percent are not the same operation.
Results are shown with up to two decimal places for readability, but the full value is used in the maths. Nothing is sent anywhere: everything runs in your browser.
Frequently asked questions
Choose 'What is X % of Y?', enter the percentage and the base value. The tool multiplies the base by the percentage divided by 100. For example, 25 % of 200 is 50.
Choose 'Percentage change from X to Y' and enter the old and new values. The change is the difference divided by the old value, times 100. A drop gives a negative percentage.
Percentage change compares a new value against a starting value and has a direction (up or down). Percentage difference compares two values against their average and is always positive.
Results are shown with up to two decimal places for readability, but the full value is used in the maths. Nothing is sent anywhere; everything runs in your browser.
If a price already includes a markup or you know the discounted price and the percentage, divide rather than subtract. For example, a price that is 80 percent of the original is the sale price divided by 0.8.
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