What is it?
The Percentage Calculator answers the five everyday percentage questions, such as “what is 18% of 2,500?” or “by what percent did my salary go up?”.
Who is it for?
Students working out marks, shoppers checking discounts and GST, employees calculating salary hikes, and shopkeepers working out margins.
How to use it
- Under What do you want to know?, pick the question you have, for example What is X% of Y?
- Type the numbers in X and Y.
- Read the answer below the boxes.
The five questions
- What is X% of Y? 18% of 2,500 = 450 (GST on a bill).
- X is what % of Y? 432 out of 500 = 86.4% (exam marks).
- Percentage change from X to Y: 80 to 100 is a 25% increase; 100 to 80 is a 20% decrease.
- Y plus X%: a salary of 40,000 plus a 10% raise = 44,000.
- Y minus X%: 2,000 minus 20% = 1,600.
The answer appears as you type; there is no Calculate button. Tap Copy result to copy it, or Share on WhatsApp to send it.
Common mistakes
- A 50% rise followed by a 50% fall doesn’t get you back: 100 → 150 → 75.
- Percent vs percentage points: an interest rate moving from 8% to 9% rises by 1 percentage point, which is a 12.5% increase.
- To remove GST from a price that includes it, don’t subtract 18%: divide by 1.18. The GST Calculator does this for you.
Errors and how to fix them
- “Enter both numbers”: X or Y is empty.
- “Y cannot be 0” or “X cannot be 0”: you can’t take a percentage of zero or a change from zero.
Open the tool: Percentage Calculator
Still stuck?
Contact support. Tell us which tool or page you were using, what you tapped, what you saw, and your phone or computer and browser (for example: Android phone, Chrome). We reply by email.
Questions, or an error not listed here?
Tell us in the comments: what you were doing, the exact message you saw, and your device and browser. We read every comment and add new fixes to this article.