Percentage Calculator
Calculate percentages, increases, decreases, differences and more — 6 modes, instant results.
📐 Quick Formulas
🔧 Related Tools
📖 How to Use the Percentage Calculator
Choose a Calculation Mode
Pick from 6 modes: find a percentage of a number, what percentage X is of Y, percentage change, difference, or add/subtract a percentage.
Enter Your Numbers
Type in the two values for your chosen mode. Press Enter or click Calculate for the instant result.
See, Copy and Track
Your answer appears instantly, colour-coded for increases (green) and decreases (red). Click Copy to copy the result. Last 10 calculations saved in history.
❓ Frequently Asked Questions
How do I calculate what percentage one number is of another?+
Divide the part by the whole and multiply by 100. For example, 30 out of 150 = (30 ÷ 150) × 100 = 20%.
How do I find a percentage of a number?+
Multiply the number by the percentage divided by 100. For example, 15% of 200 = 200 × (15 ÷ 100) = 30.
What is percentage change?+
Percentage change measures how much a value has increased or decreased relative to its original value. Formula: ((New − Old) ÷ Old) × 100. A positive result is an increase, negative is a decrease.
What is percentage difference?+
Percentage difference compares two values without a defined 'before' and 'after'. Formula: |A − B| ÷ ((A + B) ÷ 2) × 100. Useful for comparing two equal measurements.
How do I reverse a percentage?+
To find the original value before a percentage was applied, divide the current value by (1 + percentage/100) for an increase, or (1 − percentage/100) for a decrease.