Free Math Calculators
Solve math problems instantly with our collection of 40+ free online math calculators. From basic arithmetic and fractions to geometry and statistics—no sign-up required, results in seconds.
Last updated: March 2026
Percentage Calculators
Percent change, percent error, percentage points, conversions, and percentages in sports, health and finance. See also the full percentage calculator collection.
Percentage Increase Calculator
Find the percent change between two values, or a new value after a % change.
Percent Error Calculator
Compare a measured value with the accepted value for lab reports.
Percentage Point Calculator
Find the difference between two percentages in points and basis points.
Relative Change Calculator
Measure how much a value changed relative to where it started.
Average Percentage Calculator
Average several percentages, simple or weighted by sample size.
Percentage of a Percentage Calculator
Work out X% of Y%, including stacked discounts.
Fraction to Percent Calculator
Convert any fraction to a percentage and decimal.
Decimal to Percent Calculator
Convert decimals to percentages and back.
Percent to Goal Calculator
Track progress toward a target as a percentage.
Time Percentage Calculator
See what percentage of a day, week, month or year has passed.
Doubling Time Calculator
Find how long a value takes to double at a growth rate.
Slope Percentage Calculator
Convert rise and run to percent grade, degrees and ratio.
Win Percentage Calculator
Calculate win percentage with ties, and wins needed to reach a target.
Weight Loss Percentage Calculator
Calculate the percentage of body weight lost, with milestones.
On-Base Percentage Calculator
Calculate a baseball player's OBP from hits, walks and at-bats.
Slugging Percentage Calculator
Calculate slugging percentage from singles to home runs.
Arithmetic & Core Calculators
Essential calculators for everyday number crunching—percentages, averages, roots, and more.
Percentage Calculator
Calculate percentages, percentage of a number, and percentage change instantly.
Average Calculator
Find the mean, median, and mode of any set of numbers with one click.
Rounding Calculator
Round numbers to any decimal place, significant figures, or nearest whole number.
Square Root Calculator
Compute square roots, cube roots, and nth roots of any number.
Exponent Calculator
Calculate powers and exponents—raise any base to any exponent quickly.
Prime Number Calculator
Check if a number is prime and find prime factors of any integer.
Factors Calculator
List all factors and factor pairs of any positive integer instantly.
Scientific Calculator
Full-featured scientific calculator with trig, logarithms, and memory functions.
Fractions & Ratios Calculators
Add, subtract, multiply, and simplify fractions and ratios with ease.
Fraction Calculator
Add, subtract, multiply, and divide fractions with automatic simplification.
Ratio Calculator
Simplify ratios and find equivalent ratios for any two or three quantities.
Proportion Calculator
Solve proportion problems and cross-multiply to find unknown values.
GCF & LCM Calculator
Find the greatest common factor and least common multiple of two or more numbers.
Algebra Calculators
Solve equations, calculate slopes, and work through algebraic problems step by step.
Percentage Change Calculator
Calculate percentage increase or decrease between two values with direction.
Quadratic Formula Calculator
Solve quadratic equations (ax² + bx + c = 0) and find both real and complex roots.
Slope Calculator
Calculate the slope of a line from two points and find the equation of the line.
Midpoint Calculator
Find the midpoint between two coordinates in 2D or 3D space.
Geometry Calculators
Calculate area, perimeter, angles, and other geometric properties for common shapes.
Triangle Calculator
Solve any triangle—find missing sides, angles, area, and perimeter from given values.
Circle Calculator
Calculate radius, diameter, circumference, and area of a circle from any one value.
Rectangle & Square Calculator
Find area, perimeter, and diagonal of rectangles and squares instantly.
Pythagorean Theorem Calculator
Solve right triangles—find the hypotenuse or any missing side using a² + b² = c².
Area Calculator
Calculate the area of any shape—circle, triangle, rectangle, trapezoid, and more.
Statistics Calculators
Analyze data sets with statistical tools for standard deviation, probability, and more.
Standard Deviation Calculator
Calculate population and sample standard deviation and variance for any data set.
Statistics Calculator
Comprehensive statistical analysis: mean, median, mode, range, and quartiles.
Probability Calculator
Calculate single and compound event probabilities, combinations, and permutations.
Distance Calculator
Calculate the distance between two points using the distance formula in 2D or 3D.