Percentage Calculator
We have added real-life examples to every card, so it is easier to see which one fits your question. Type in your numbers and the example changes to match them.
Tips, tax and shares of an amount
A tip of 15% on a bill of $80 is $12.
Marks, grades and shares as a percentage
Getting 42 out of 50 in a test is 84%.
Reverse percentage: work out the original price
Saving $30 with a discount of 20% means the original price was $150.
Add a percentage (pay rise, tax, markup)
A pay rise of 5% on a salary of $30,000 takes you to $31,500.
Take off a percentage (sales, discounts)
A sale of 25% off $80 brings the price down to $60.
Percentage increase or decrease
Going from $800 to $880 is an increase of 10%.
How far apart are two numbers?
$90 and $110 are 20% apart.
Weight loss or gain percentage
Going from 90 kg to 81 kg is a weight loss of 10%.
Win percentage
12 wins and 8 losses is a win rate of 60%.
Two discounts in a row
30% off, then an extra 10% off, is 37% off in total, not 40%.
Profit, markup and margin
Buying at $60 and selling at $100 gives a margin of 40% and a markup of 66.67%.
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Pick the card that matches what you are working out, type in two numbers, and the answer shows straight away.
Common mistakes
- Taking 20% off and then adding 20% back. You do not end up where you started.
- Adding two discounts together. 20% off and then another 10% off is not 30% off.
- Working out a change from the wrong starting number. It is always the old value.
- Mixing up percent and percentage points.
Questions
How do I calculate percentage increase or decrease?
New number minus old number, divided by the old number, times 100. From 50 to 75 that is 25 ÷ 50 × 100 = a 50% increase. A negative answer is a decrease.
How do I work out what percentage pay rise I got?
Divide the extra money by your old pay and multiply by 100. $30,000 to $31,500 is $1,500 ÷ $30,000 × 100 = 5%.
How do I calculate weight loss as a percentage?
Use the same sum as percentage change. From 90 kg to 81 kg is −9 ÷ 90 × 100 = −10%, so you have lost 10% of your starting weight.
How do I work out the original price before a discount?
This is a reverse percentage. If the price is $80 after 20% off, then $80 is 80% of the original, so the original was $80 ÷ 0.8 = $100.
How do I calculate a win percentage?
Wins divided by games played (wins plus losses), times 100. 12 wins and 8 losses is 12 ÷ 20 × 100 = 60%. Draws are not counted, so add them in yourself if your record includes them.
Why does taking 20% off and then adding 20% back not get me to where I started?
The second 20% is worked out on a smaller number. 100 less 20% is 80, and 80 plus 20% is 96. To undo a 20% drop you need to add 25%.
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