Percentage Calculator: Solve Any Percentage Problem

Our Percentage Calculator handles four common percentage calculations: finding percentages of numbers, calculating what percentage one number is of another, determining percentage increases and decreases, and solving reverse percentage problems. Whether you're calculating discounts, tips, taxes, grades, or business metrics, this tool provides accurate results instantly.

What This Calculator Does

The Percentage Calculator supports four calculation modes:

• What is X% of Y?: Calculate what percentage of a number equals (e.g., "What is 15% of $200?").
• X is what % of Y?: Find what percentage one number represents of another (e.g., "25 is what percentage of 100?").
• X increased/decreased by Y%: Calculate the result when a number changes by a percentage (e.g., "$100 increased by 10%").
• X is Y% of what number?: Reverse percentage calculation (e.g., "30 is 20% of what number?").

This calculator is perfect for discounts, tips, markups, tax calculations, grade percentages, and business growth metrics.

How to Use It

1. Select calculation mode: Choose from the four calculation types in the dropdown menu.
2. Enter values: Input the required numbers based on your selected mode.
3. For percentage changes: Select whether you're calculating an increase or decrease.
4. Click "Calculate" to see your results instantly.

You can switch between modes at any time to solve different percentage problems.

Interpreting Your Results

• Result: The calculated answer based on your selected mode.
• Supporting values: Additional context like original values, change amounts, or percentages depending on the calculation mode.
• Percentage values: Displayed with the % symbol for clarity.

Common Mistakes to Avoid

• Confusing percentage and decimal: Enter percentages as whole numbers (e.g., 15 for 15%, not 0.15).
• Mixing up part and whole: In "X is what % of Y?" mode, make sure X is the part and Y is the whole.
• Forgetting increase vs decrease: When calculating percentage changes, ensure you've selected the correct direction.
• Using wrong mode: Double-check that you've selected the calculation mode that matches your problem type.

Keep Learning

Explore these guides to master percentage calculations:

• Understanding Percentage Basics: How Percentages Work
• Calculating Discounts and Sales: Save Money with Math
• Percentage Increase and Decrease: Business and Finance Applications
• Reverse Percentage Problems: Working Backwards
• Common Percentage Mistakes and How to Avoid Them

Sources

• Khan Academy – Percentage basics and applications
• National Council of Teachers of Mathematics – Percentage calculation methods