Percentage Calculator
Get your percentage calculated instantly, for free.
The Percentage Calculator takes two numbers and instantly calculates the percentage relationship between them. No signup, no spreadsheet formulas — just enter your numbers and get an accurate result.
Manual calculations are easy to get wrong, especially with percentages, dates or fees involving multiple steps. This calculator handles the math precisely so you can focus on the decision the number is informing.
How to Use the Percentage Calculator
- Enter the required values
- Click Calculate
- Review your result instantly
Best Practices
- Double-check input units (currency, dates, percentages) match what's expected
- Use the result as a planning estimate — confirm exact figures with official statements where money is involved
- Bookmark this tool for quick repeated calculations
This tool is free to use with no signup required.
Frequently Asked Questions
How do I calculate what percentage one number is of another?
Divide the first number by the second, then multiply by 100. For example, 25 is what percent of 200? (25 ÷ 200) × 100 = 12.5%.
How do I calculate a percentage of a number?
Multiply the number by the percentage (as a decimal). For example, 20% of 150 = 150 × 0.20 = 30.
How do I calculate percentage increase or decrease?
Subtract the original value from the new value, divide by the original value, then multiply by 100 — a positive result is an increase, negative is a decrease.
Is this tool free to use?
Yes, completely free with no signup, no limits and no software to install.
Is my data saved anywhere?
No — calculations run in your browser and the values you enter are not stored or sent to a server.
How do I reverse-calculate the original number from a percentage?
If you know that X% of a number equals Y, divide Y by X (as a decimal) to find the original number: Original = Y ÷ (X ÷ 100).
Is this useful for calculating tips or discounts?
Yes — percentage calculations are the basis for tip amounts, discounts, sales tax, and many everyday financial calculations.
What's the difference between percentage points and percent change?
Percentage points measure the raw difference between two percentages (e.g., 40% to 50% is a 10 percentage point increase), while percent change measures the relative change (that same move is a 25% increase relative to the starting 40%).
Can I calculate percentages with negative numbers?
Yes, the same formulas apply — the calculator handles negative values in percentage-of and percentage-change calculations correctly.
Is this useful for calculating grade percentages?
Yes — dividing points earned by points possible and multiplying by 100 is exactly the calculation used for test and assignment grade percentages.
