Percentage Calculator

Calculate percentages instantly: percent of a number, what percent one value is of another, and percentage increase or decrease.

Handle the most common percentage questions in one place

Use this free online percentage calculator for prices, discounts, analytics, finance, grades, markups, or quick everyday math without switching between multiple smaller tools.

Percentage Value

Choose a percentage mode and enter two values to calculate the result instantly.

Ready

Enter values to calculate a percentage.

The main percentage answer will appear here as soon as the current inputs are valid.

Use the mode switch to move between percent-of, percent relationship, and increase or decrease calculations.

Choose the percentage mode that matches your question.
Enter the two values needed for the current calculation.
If you are adding or subtracting a percentage, choose increase or decrease.
Review the main answer and the supporting values in the result card.
Use Example to load a sample calculation or Clear to reset the tool.

What is 25% of 200?
45 is what percent of 180?
How do you increase 80 by 10%?

This calculator combines the most common percentage workflows into one page. You can calculate a percentage of a value, find what percent one number is of another, or adjust a value up or down by a percentage without switching to multiple smaller tools.

A percentage calculator is useful for discounts, taxes, markups, performance reports, grading, budgeting, pricing, and quick everyday comparisons. Instead of rewriting the formula manually, you can choose the matching mode and review the answer instantly.

Percentage questions often sound similar while needing different formulas. A mode-based calculator makes the intent explicit, so it is easier to answer questions like `what is 20% of 80`, `35 is what percent of 140`, or `increase 250 by 12%` without using the wrong formula.

This calculator can answer common percentage questions such as `What is 20% of 150?`, `45 is what percent of 180?`, `Increase 200 by 15%`, and `Decrease 500 by 10%` without switching formulas by hand.

Can this calculate what percent one number is of another?

Yes. Switch to the `X is what % of Y?` mode, enter both values, and the tool returns the percentage relationship.

Can I use it for percentage increase and decrease?

Yes. The third mode lets you add or subtract a percentage from a starting value.

What happens if the base value is 0?

For modes that divide by the base value, the tool shows a clear error instead of returning an invalid percentage.

Percentage Calculator

Calculate percentages instantly

Handle the most common percentage questions in one place

Calculated percentage result

How to use the percentage calculator