Percentage Calculator
Work out what percent of a number is, percentage increase or decrease and the change between two values. Free, instant and runs in your browser.
Answer
Work out percentages without the algebra
Three questions cover almost every percentage problem: what is X% of Y, what percent of Y is X, and what is the percentage change from A to B. This calculator answers all three directly, so you never have to rearrange a formula — pick the phrasing that matches your question and fill in the two numbers you know.
Percentage change trips people up because the direction matters: going from 50 to 75 is a 50% increase, but going from 75 to 50 is a 33.3% decrease. The calculator always divides by the starting value, which is the convention used for price changes, salary raises and statistics.
Everything is computed in your browser as you type, with no rounding surprises — results show enough decimal places to be exact for money and percentages alike.
Frequently asked questions
How is percentage change calculated?
Subtract the starting value from the end value, divide by the starting value, and multiply by 100. From 80 to 100 is (100 − 80) / 80 × 100 = 25% increase; from 100 to 80 is a 20% decrease, because the divisor is now 100.
How do I find what percent one number is of another?
Divide the part by the whole and multiply by 100. Use the "X is what % of Y" mode: 45 out of 60 is 75%.
How do I find the original price before a discount?
Use the "Find the original" mode. Enter the known amount and the percentage it represents: if 30 is 15% of the original, the original is 30 ÷ 15 × 100 = 200.
What is the difference between a percentage change and percentage points?
A rate going from 4% to 6% has risen by 2 percentage points but by 50% in relative terms. This calculator reports the relative change; subtract the two figures yourself if you want points.
Why does it show no result?
One of the two fields is empty or the calculation would divide by zero, such as asking what percent a number is of 0, or the change from 0 to anything. Enter a non-zero base and the answer appears.
How do I convert marks or CGPA to a percentage?
Pick "Marks to %" and enter the marks obtained and the total: 432 out of 500 is 86.4%. For CGPA, pick "CGPA to %", which multiplies by 9.5 (the CBSE factor) by default; change the multiplier if your board or university uses a different one.