Online Percentage Calculator | Best tool for Students

Online Percentage Calculator

Calculate percentages, percentage change, increase/decrease — fast and accurate. Created by Bishhnu Banerji.

Select calculation What is X% of Y X is what percent of Y Percentage change (increase/decrease) Add percentage to a number Subtract percentage from a number

Value A

Enter the primary number (for percent of: the percent; for change: old value).

Value B

Enter the second number (for percent of: the base; for change: new value).

Result

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Detailed explanation will appear here.

Quick examples:

• What is 20% of 150 → 30
• 50 is what percent of 200 → 25%
• From 100 to 120 → +20% (increase)

We do not store any calculation data. All inputs remain in your browser session and are cleared when you clear the form. For privacy, nothing is uploaded to a server.

Created by Bishhnu Banerji

Version 1.0

How to use this Percentage Calculator

1. Select the calculation type from the dropdown.
2. Enter values for Value A and Value B according to the help text below each field.
3. Click Calculate. Result and an explanation will show on the right panel.
4. Use Clear to reset inputs. Click Copy Result to copy the main numeric output.

Error handling & auto-corrections

This tool validates inputs and attempts to correct common mistakes automatically: empty fields are treated as zero with a helpful note; extremely large or scientifically formatted numbers are parsed; division-by-zero is detected and prevented with suggestions. All errors are shown clearly and non-destructively so you can adjust inputs.

Disclaimer

We do not store any data. All calculations are performed in your browser and cleared on refresh or when you click Clear. Use the results at your own discretion — not financial or legal advice.

Frequently asked questions (FAQ)

Q: Does the tool upload my numbers?

No. All operations run locally in your browser.

Q: Can I use this on mobile?

Yes, it is responsive and works across desktops, tablets and phones.

Q: Can I copy results?

Yes, use the Copy Result button. Nothing is stored or shared.

© Bishhnu Banerji — Online Percentage Calculator. We do not store any calculation data.