Clear maths for everyday questions
Percentage Calculator is an independent educational website built to make common percentage operations easier to use and understand. We combine interactive tools with formulas and original worked examples so you can check both the answer and the method.
How our tools work
Calculations run in your browser using JavaScript. We show the substituted formula, let you change the displayed decimal precision, and explain undefined or unsupported inputs rather than silently treating them as valid results.
Our editorial approach
Guides focus on the question a formula answers, its assumptions and a checkable example. We distinguish percentage change from symmetric percentage difference and percentage points. We do not present an arbitrary grade conversion or a tax estimate as a universal rule.
Accuracy and corrections
Software and educational content can contain mistakes. Please use our contact page to report an incorrect example, confusing label or calculator issue. Include the calculator name, input values and the result you expected. Check important outcomes independently.