Percentage Calculator
Calculate percentages — what is X% of Y, X is what % of Y, percentage increase/decrease, and more.
History
Calculate percentages easily. Part of the freeq.one tools suite.
About This Tool
Percentages are everywhere in everyday life — tips, discounts, taxes, interest rates, grades, statistics, and more. A percentage represents a fraction of 100, making it easy to compare ratios and proportions. This calculator handles four common types of percentage problems: finding X% of Y, determining what percentage X is of Y, calculating percentage increase or decrease, and adding or subtracting a percentage from a value. It also features quick percentage buttons for common values like 10%, 15%, 20%, and 25%.
Each calculation mode shows the formula used to derive the result, helping you understand the math behind the number. This is especially useful for students learning percentages or for professionals who need to verify calculations. The tool also stores your calculation history with pinning support, so you can refer back to past results or reuse frequently needed percentage calculations without re-entering values.
Common Use Cases
- Calculating restaurant tips and splitting bills among friends
- Figuring out sale discounts and tax amounts while shopping
- Computing grade percentages and test scores for academic tracking
- Determining percentage increases for salary raises, price hikes, or investment returns
- Calculating markup and margin percentages for retail and e-commerce pricing
- Computing statistical percentages for data analysis and reporting
Pro Tips
- For a 15% tip, multiply the bill by 0.15; for 20%, multiply by 0.20 — use the quick buttons for instant results
- Percentage change formula: (new value - old value) / old value × 100 — positive means increase, negative means decrease
- To find the total after adding tax, multiply the base price by (1 + tax rate) — e.g., 1.13 for 13% tax
- Pin your most-used percentage calculations to the history for quick access without re-entering values
Frequently Asked Questions
- How do I calculate a percentage of a number?
- To find X% of Y, multiply Y by (X / 100). For example, 15% of 200 is 200 × (15 / 100) = 30. Use the "X% of Y" mode in this calculator for instant results.
- How do I calculate percentage change?
- Percentage change = (new value - original value) / original value × 100. A positive result indicates an increase, while a negative result indicates a decrease. Use the "Percentage Change" mode for automatic calculation.
- What is the difference between percentage increase and percentage points?
- Percentage increase is relative to the original value. Percentage points refer to the absolute difference between two percentages. For example, an interest rate rising from 5% to 7% is a 2 percentage point increase but a 40% increase.
- How do I calculate what percentage one number is of another?
- To find what percentage X is of Y, divide X by Y and multiply by 100. For example, 30 out of 200 = (30 / 200) × 100 = 15%. Use the "X is what % of Y" mode in this tool.
Also check out our Random Number Generator for more number tools. Part of the FreeQ.One tools suite.