Result
0
0% of 0 = 0
%
Tip: also handy for tips, discounts and taxes — e.g. 18% of 999 for GST.
Result
0%
0 is 0% of 0
Y can't be zero — division by zero is undefined.
Great for marks, scores and shares — e.g. 45 is what % of 60?
Result
0%
No change
The old value can't be zero — percentage change is undefined.
Track price rises, salary hikes or weight changes — sign shows increase or decrease.
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Percentage Calculator — Free Online Tool
Instant answers — everything happens right in your browser.
How it works
- 1Choose a mode — X% of Y, X is what % of Y, or % change.
- 2Type your numbers — the answer appears as you type.
- 3Read the formula under the result to see the working.
Frequently asked questions
Are my numbers private?
Yes. Every calculation runs in your browser with JavaScript — nothing you type is sent to any server or stored anywhere.
What does the % change mode show?
How much a value grew or shrank between two numbers — for example 100 → 150 is a +50% increase, 100 → 80 is a −20% decrease. The formula line shows an arrow and the word "increase" or "decrease".
Why does it say "undefined" for some inputs?
Division by zero has no answer, so "X is what % of Y" with Y = 0 and "% change" with an old value of 0 show a warning instead of a number.