Percentage Calculator
Find a percentage, compare values, or calculate a percentage change.
Choose the sentence that matches your question
Enter the two numbers you know. Your answer appears beside the formula.
Find what percent one number is of another
Find the percent increase or decrease
Find the percent difference
Choose the sentence that matches your question. Only fill in its two number boxes.
Choose the percentage question that matches your numbers
Choose the sentence that matches your problem and enter the two numbers you know. The calculator leaves each formula separate so you can see which result answers your question.
The percentage formulas
Part = (percentage ÷ 100) × whole. Percent = (part ÷ whole) × 100. Percent change = |new − start| ÷ |start| × 100, labeled increase or decrease. Percent difference = |A − B| ÷ ((|A| + |B|) ÷ 2) × 100.
Example: 20% of 500
20% of 500 is (20 ÷ 100) × 500 = 100.
Percent change and percent difference are different
Percentage change uses the starting value as its base. Percent difference instead compares two values against their average, so the two answers can differ.
When each percentage method is useful
Check a sale discount, compare two measurements, or see how much a value rose or fell.
Questions and answers
How do I find a percentage of a number?
Convert the percentage to a decimal by dividing by 100, then multiply by the number.
How do I calculate percentage change?
Subtract the original value from the new value, divide by the original, then multiply by 100. A negative result is a decrease.