How to use the Percentage Calculator tool
- Find the calculation that matches your question.
- Type your numbers into its boxes.
- Read the answer, which updates as you type.
The formulas
| Question | Formula | Example |
|---|---|---|
| What is P% of X? | P ÷ 100 × X | 20% of 150 = 30 |
| A is what % of B? | A ÷ B × 100 | 30 of 150 = 20% |
| Change from A to B | (B − A) ÷ A × 100 | 80 → 100 = +25% |
| X increased by P% | X × (1 + P ÷ 100) | 200 + 15% = 230 |
| X decreased by P% | X × (1 − P ÷ 100) | 200 − 15% = 170 |
Percent vs percentage points
If an interest rate goes from 2% to 3%, it rose by 1 percentage point, but by 50 percent. News reports and offers often mix these up, so check which one is meant.
Frequently asked questions
How do I calculate a percentage increase?
Subtract the old value from the new one, divide by the old value and multiply by 100. From 80 to 100 is (100 − 80) ÷ 80 × 100 = 25%.
Why isn’t a 20% rise followed by a 20% fall back to the start?
The fall is taken from the larger number. 100 + 20% = 120, and 120 − 20% = 96.
Are my files uploaded to a server?
No. HushConverts converts everything with code that runs in your browser, so your text and files stay on your device. You can even use most tools offline once the page has loaded.
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