Percentage Calculator
Percentages show up in tips, discounts, tax, grades and interest. This solves the three questions people ask most: what is a percentage of a number, what percent one number is of another, and what whole a part came from.
Your numbers
Result
- In words
- 10% of 200 = 20
| Step | Detail |
|---|---|
| Operation | What is A% of B |
| Formula | 10% × 200 ÷ 100 |
| Result | 10% of 200 = 20 |
What is A% of B
Multiply the number by the percentage and divide by 100: B × A ÷ 100. So 10% of 200 is 200 × 10 ÷ 100 = 20. A quick shortcut for 10% is to move the decimal one place; for 1%, move it two.
A is what percent of B
Divide the part by the whole and multiply by 100: A ÷ B × 100. If 20 out of 200 questions were correct, that is 20 ÷ 200 × 100 = 10%. This is the mode for test scores, completion rates and "what share is this".
Finding the whole from a part
If A is B% of some number, recover the whole with A ÷ (B ÷ 100). When $30 is 15% of a total, the total is 30 ÷ 0.15 = $200. Useful for reversing a tip, tax or commission back to the base amount.
Frequently asked questions
Sources
Embed this calculator
Copy the code and paste it into your site or blog. Credit with a link back to Contania is included, and the height adjusts itself.
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<script>window.addEventListener("message",function(e){if(e.data&&e.data.type==="contania:embed-height"){var f=document.querySelector('iframe[src="https://contania.app/embed/math/percentage"]');if(f){f.style.height=e.data.height+"px"}}});</script>Related calculators
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