10 calculators · runs entirely in your browser
Any two numbers.
The third, instantly.
Fill in any two boxes and the third works itself out. What is 15% of 200? 30 is what percent of 120? 45 is 9% of what? One calculator answers all three.
15% of 200 is 30
Show working
Y = P × X ÷ 100= 15 × 200 ÷ 100= 30
Tip: ↑ ↓ nudge a number · ⌘K finds any calculator
In plain words
Ask it the way you’d say it.
The calculators
10 calculators, one idea.
Percentages
Percentage calculator
Fill in any two of the three boxes and the third works itself out: what is P% of X, X is what percent of Y, or X is P% of what.
15% of 200 is 30
Percentage change calculator
How much did something go up or down, in percent? Enter the old and new values, or a value and a change to find the other.
From 80 to 100 is a 25% increase
Increase or decrease by percent
Add or take away a percentage: a 10% hike on a salary, 18% off a price, or find what the number was before the change.
50,000 increased by 12% is 56,000
Percentage difference calculator
Compare two numbers when neither is the starting point. The difference is measured against their average, so the order doesn’t matter.
150 and 120 differ by 22.22%
Percent, decimal & fraction converter
Type a percent, a decimal or a fraction and see the other two. Fractions are simplified, so 37.5% becomes 3/8.
37.5% = 0.375 = 3/8
Money & marks
Discount calculator
Find the sale price, how much you save, or what discount you’re really getting. Any two of price, discount and final price.
2,499 with 40% off is 1,499.40
GST calculator
Add GST to a price or take it out of an inclusive one, with the CGST and SGST split. Works for VAT and any sales tax too.
1,000 plus 18% GST is 1,180
Profit margin calculator
Price a product for the margin you want, or check the margin and markup on what you already sell.
Selling at 800 from a cost of 600 is a 25% margin
CAGR calculator
The steady yearly growth rate that turns a starting value into an ending value. Fill in any three of the four boxes.
100,000 growing to 250,000 in 5 years is 20.11% a year
Marks percentage calculator
Turn exam marks into a percentage, or work out how many marks you need to reach a target score.
432 out of 500 is 86.4%
Any box can be the answer
Type into whichever boxes you know. The one you touched least recently becomes the answer, so you can work forwards or backwards.
Shows its working
Every answer comes with the formula and the numbers plugged in, so you can check it or copy the method into your homework.
Private, with lakh & crore
Everything runs on your device and nothing is sent anywhere. Switch digit grouping to 10,00,000 if that’s how you read numbers.
Questions, answered.
How do I calculate a percentage of a number?
Multiply the number by the percentage and divide by 100. 15% of 200 is 15 × 200 ÷ 100 = 30. Type the two numbers you know above and the third box shows the answer.
What’s the difference between percentage change and percentage difference?
Percentage change compares a new value with an old one, so the order matters (80 → 100 is +25%). Percentage difference compares two values on equal footing using their average, so the order doesn’t matter.
Why doesn’t a 20% rise and a 20% fall cancel out?
Each percentage is taken from a different starting point. 100 up 20% is 120, but 20% of 120 is 24, so coming back down lands on 96.
Can I share a calculation?
Yes. On each calculator’s own page the address bar updates as you type. Use “Copy link” and whoever opens it sees the same numbers.
Is anything I type sent to a server?
No. Percent is a static site and every calculation is plain JavaScript running in your browser.