Math

About Our Math Calculators

Our math calculators cover everything from primary-school fractions to university statistics. Students use them to check homework, parents use them to help explain a method, and professionals reach for them when a spreadsheet would be overkill. Whether you need to simplify 18/24, find the roots of a quadratic, or work out the standard deviation of a data set, there is a dedicated tool that gives a clean answer without the arithmetic slips that creep in by hand.

Most popular tools

• Scientific Calculator — Handles trigonometry, logarithms, powers and roots in one place.
• Fraction Calculator — Adds, subtracts, multiplies and divides fractions and mixed numbers.
• Percentage Change Calculator — Shows the percentage increase or decrease between two values.
• Standard Deviation Calculator — Measures how spread out a set of numbers is.
• Quadratic Formula Calculator — Solves equations of the form ax² + bx + c = 0.
• Square Root Calculator — Finds square roots of any positive number.
• Average Calculator — Gives the mean of a list of numbers.
• Triangle Calculator — Solves missing sides and angles of a triangle.

How to choose the right calculator

• Numbers and arithmetic: Fraction, Fraction Simplifier, Long Division, Rounding, Exponent, Scientific Notation, Significant Figures, Prime Number Checker, GCF and LCM.
• Algebra: Quadratic Formula, Slope, Matrix and Ratio.
• Geometry: Area, Rectangle Area, Triangle, Circumference and Volume.
• Statistics and chance: Average, Weighted Average, Standard Deviation, Probability, Random Number Generator and Dice Roller.
• Applied: Speed, Subnet and Refractive Index.

Quick answers

Sample or population standard deviation? Divide by n − 1 when your data is a sample of a larger group, and by n when you have every member of the population. The sample version is slightly larger.

Percentage change or percentage points? A rate moving from 4% to 5% rises by one percentage point, but that is a 25% increase. The Percentage Change Calculator gives the second figure.

How are GCF and LCM related? For two positive whole numbers, GCF × LCM equals the product of the numbers. For 12 and 18, 6 × 36 = 216 = 12 × 18.

All of these math calculators are free, run in your browser and need no sign-up or download.