Percentage Calculator
Work out what a percentage of an amount is, with the result as you type.
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The percentage calculator answers the most common question of all: how much a given percentage of an amount is. Type the percentage and the amount and the result appears instantly.
How it is calculated
A percentage is a fraction out of a hundred, so you divide by 100 and multiply:
| Question | Operation | Result |
|---|---|---|
| 20% of 250 | 0.20 × 250 | 50 |
| 21% of 1,000 | 0.21 × 1,000 | 210 |
| 15% of 47.50 | 0.15 × 47.50 | 7.13 |
Two shortcuts that work in your head: 10% is moving the decimal point one place left, and 5% is half of that 10%. Between them you can build almost any round percentage: 15% is 10% + 5%, 20% is 10% twice.
The commutativity trick
4% of 75 and 75% of 4 give exactly the same answer: 3. Since both are the same multiplication, you can always flip the calculation round if one side is easier. 16% of 25 looks awkward; 25% of 16 is obviously 4.
How to use Percentage of an amount
- 1
Enter the percentage
Put the percentage you want to work out in the first field, for example 20 for a fifth or 15 for a tip.
- 2
Enter the amount
In the second field put the amount it applies to, without a currency symbol or thousands separators.
- 3
Read the result instantly
The calculation runs automatically as soon as both fields are filled, with no button to press.
- 4
Copy the result
Use the copy button to take the figure with you.
Frequently asked questions
How do you work out X% of an amount?
Divide the percentage by 100 and multiply by the amount. 20% of 250 is 0.20 × 250 = 50. This calculator does that as you type.
How do I work out a discount and the final price?
Enter the discount percentage and the original price: the result is what you save. Subtract it from the original price for the final one. 30% off £80 is £24 saved and £56 to pay.
How do I work out a tip?
Put in the percentage you want to leave and the bill total. 10% of £47.50 is £4.75.
Can I use a percentage greater than 100?
Yes. 150% of 40 is 60, and 250% of 40 is 100. There is no limit: a percentage is just a multiplier.
Does it work for VAT or sales tax?
It gives you the tax on a net price: 20% VAT on £50 is £10. To take the tax out of a price that already includes it, do not subtract the percentage; divide by 1 plus the rate instead. £60 including 20% VAT is £60 / 1.2 = £50 net.