Work out percentages, discounts, tax and tips — with the working shown.
Every everyday percentage question in one place: what X% of Y is, what proportion one number is of another, percentage increase and decrease, sale prices, adding or removing tax, and splitting a bill with a tip.
Everything you enter stays in this browser tab. Nothing is sent to our servers, logged or stored.
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What Percentage Calculator supports
Basics
X% of Y
X is what % of Y
Percentage increase or decrease
Money
Discount & sale price
Add or remove tax / VAT
Tip & bill splitting
About Percentage Calculator
Percentages come up constantly and are surprisingly easy to get backwards. The classic trap: a price that rises 20% and then falls 20% does not return to where it started — it ends up 4% lower, because the second percentage is taken from a bigger number.
Each mode here shows the arithmetic, not just the answer. Seeing that a 20% discount on £80 is £80 × 0.20 = £16 saved makes the result checkable, and makes the method stick for next time.
The tax mode works in both directions, which is the one people most often need and most often cannot find. Adding VAT to a net figure is easy; recovering the net figure from a VAT-inclusive total means dividing by 1.20, not subtracting 20%.
How to calculate a percentage
1
Pick the question you are asking
Percent of a number, percentage change, discount, tax or tip.
2
Fill in the numbers
The result updates as you type — there is nothing to submit.
3
Check the working
Each answer shows the calculation behind it so you can verify it.
The mistakes worth knowing about
Up 20% then down 20% is not back to the start — it is 4% below, because the decrease applies to a larger number.
Removing 20% tax from a total means dividing by 1.2, not subtracting 20%. Subtracting gives you 4% too little.
Percentage points and percent are different: going from 10% to 15% is a rise of 5 percentage points, but a 50% increase.
A 50% markup is a 33.3% margin. Markup is measured against cost, margin against selling price.
Frequently asked questions
How do I work out a percentage of a number?
Divide the percentage by 100 and multiply. 15% of 240 is 0.15 × 240 = 36. The tool shows this working alongside the answer so you can check it.
Why doesn't a 20% rise followed by a 20% fall return to the start?
Because the second percentage is taken from a larger number. £100 rises to £120, and 20% of £120 is £24, leaving £96. You end up 4% below where you began.
How do I remove VAT from a total?
Divide by 1 plus the rate — for 20% VAT, divide the total by 1.2. Subtracting 20% instead is a common error that leaves you about 4% short of the real net figure.
What is the difference between percent and percentage points?
If a rate moves from 10% to 15%, that is a rise of 5 percentage points but a 50% increase. Mixing the two is a frequent source of misleading statistics.
How much should I tip?
Custom varies by country: 15–20% is typical in the United States, while in much of Europe service is included and rounding up is normal. The calculator handles any percentage and splits the bill between any number of people.