Percentage Calculator
Answer the three everyday percentage questions in one place: what is 20% of 150, what percent is 30 of 150, and by how much did a value change in percent.
Runs in your browser
How to use
- Pick the question you want answered.
- Enter the two numbers X and Y.
- Read the result — it updates as you type.
How it works
X% of Y = X ÷ 100 × Y. “X is what percent of Y” = X ÷ Y × 100. Percentage change from X to Y = (Y − X) ÷ |X| × 100, positive for an increase and negative for a decrease.
You can type numbers with a decimal point or a comma (12.5 or 12,5) and with thousands separators.
Examples
- Tip
- 15% of 64 = 9.60.
- Exam score
- 42 out of 60 = 70%.
- Price change
- From 80 to 92 = +15%.
- Discount then tax
- A 30% discount on 250 gives 175; adding 20% tax on that gives 210. Order matters only for the intermediate figures — the total is the same either way.
Common uses
- Shopping discounts and tips
- Grades and test scores
- Sales and budget reports
Privacy & security
This tool runs entirely in your browser. Your files and text are never uploaded to our servers — processing happens on your device and results are created locally. How each tool handles files
Frequently asked questions
How do I calculate a percentage of a number?
Multiply the number by the percentage and divide by 100. 20% of 150 = 150 × 20 ÷ 100 = 30.
Why is a 50% drop followed by a 50% rise not back to the start?
Because the second percentage applies to a smaller base: 100 → 50 → 75.
How do I remove a percentage, for example VAT?
Divide, don't subtract. To take 20% VAT off a price of 120, compute 120 ÷ 1.20 = 100. Subtracting 20% of 120 would give 96, which is wrong.
What's the difference between percent and percentage points?
Going from 5% to 7% is a rise of 2 percentage points, but a 40% increase. Rates of interest, unemployment and market share are compared in points to avoid that ambiguity.
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