Percentage Calculator
Calculate percentages, percentage increase/decrease, and what percentage one number is of another.
Disclaimer
This calculator provides estimates for general information purposes only. Results are based on standard formulas and may not reflect your individual circumstances. Always consult a qualified professional for advice specific to your situation.
Frequently Asked Questions
How do you calculate a percentage of a number?
How do you calculate percentage change?
What is Percentage?
A percentage calculator is a multipurpose maths tool for working with percentages. It can find a percentage of a number, calculate percentage change between two values, or determine what percentage one number is of another.
How this calculator works
Three modes cover the most common percentage calculations: 'X% of Y' finds a specific percentage of any number (e.g., 15% of 200 = 30). '% Change' calculates the percentage increase or decrease between two values — useful for comparing prices, salaries, or investment returns. 'X is what % of Y' determines the ratio as a percentage — useful for working out tax rates, discounts, or proportions. The quick reference table shows mental shortcuts for common percentages (10% = divide by 10, 25% = divide by 4, GST 10% = divide by 11).
All calculations are performed in your browser — your data never leaves your device. Results are for general guidance only and should not be considered professional financial advice.
Built and maintained by Konstantin Iakovlev. Data sourced from the ATO and official Australian government sources.