Choose the correct percentage question
“15% of 850” and “15 is what percent of 850” use different formulas and produce different kinds of answers.
Math
Percentage calculator
Solve the most common percentage questions in one place.
Clear and dependable
How to use this calculator
Choose one of the four percentage questions, then enter X and Y. For an adjustment, choose whether to increase or decrease Y.
Understanding the result
The answer is written as a complete sentence and includes the exact calculation used. Percentage change treats the first value as the original baseline.
Avoid these errors
Common mistakes
Adding 20% is not reversed by subtracting 20%
The second percentage uses a different base. Divide by 1.2 to reverse a 20% increase exactly.