How it works
A percentage is a ratio out of 100. Use any two known values to find the third, or compare two numbers with difference and change modes.
amount = (percent / 100) × whole
When to use
Use Proportion for any two of percent / whole / amount. Switch to Phrases for everyday questions like “What is 15% of…?”.
How to use this tool
- Enter your values in the fields above.
- Review the formula and any mode options for your problem.
- Read the result and the step-by-step solution.
Use Proportion for any two of percent / whole / amount. Switch to Phrases for everyday questions like “What is 15% of…?”.
Frequently asked questions
- What is the Percentage Calculator?
- A percentage is a ratio out of 100. Use any two known values to find the third, or compare two numbers with difference and change modes.
- How do I use the Percentage Calculator?
- Enter the required values, then calculate. The Percentage Calculator shows results, formulas, and step-by-step work when available. No account is required.
- What formula does the Percentage Calculator use?
- amount = (percent / 100) × whole
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