Math & Science

Percentages, fractions, algebra, geometry and physics helpers for homework and work.

Free math & science calculators from CalculatorWonder. Every tool below runs instantly in your browser, states the formula and assumptions behind the answer, and never stores what you type.

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Percentage Calculator

Percentage of a number, one number as a percentage of another, and percentage change.

Three of the most common percentage questions in one place: what a percentage of a value is, what share one value is of another, and how much something rose or fell in percentage terms.

Percentages turn up everywhere — discounts, tax rates, tips, exam scores, pay rises and survey results — yet they are easy to get wrong in your head. The Percentage Calculator bundles the three most common questions into one tool: what a given percentage of a number is, what share one number is of another, and how much something increased or decreased in percentage terms.

Other categories

• Money & Finance — Mortgages, loans, interest, salary and long-term planning maths, worked out in seconds.
• Health & Fitness — Body metrics, energy needs and everyday wellbeing numbers explained in plain language.
• Time & Date — Ages, gaps between dates, countdowns and time zone questions, answered exactly.
• Conversion — Switch between units of length, weight, temperature, volume and currency.
• Business & Productivity — Pricing, margin, break-even and return calculations for people running things.
• Household & Lifestyle — Rent, running costs, utilities and kitchen maths for the place you live in.
• Vehicle & Travel — Fuel economy, car finance and trip budgets before you turn the key.
• Education & Learning — Grades, averages and study finance tools for students and teachers.

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