Algebra
FreeQuadratic Formula Calculator
Solve any quadratic equation ax² + bx + c = 0 for real or complex roots, with the discriminant and every step of the formula shown.
Open tool FreeSystem of Equations Solver
Solve a system of two linear equations with two unknowns using Cramer's rule, with the determinant and every step shown.
Open tool FreeLog Calculator
Calculate a logarithm in any base, including log base 10, natural log (ln) and log base 2, with the change-of-base formula shown.
Open tool FreeProportion Calculator
Solve for the missing value in a proportion (a/b = c/d) using cross-multiplication, with each step of the algebra shown.
Open toolNumber Theory
FreeGCF Calculator
Find the greatest common factor of two or more numbers, with every Euclidean-algorithm reduction step shown.
Open tool FreeLCM Calculator
Find the least common multiple of two or more numbers, using the GCF relationship with every pairwise reduction step shown.
Open tool FreeRatio Calculator
Simplify a ratio to lowest terms or solve a proportion a:b = c:d for a missing value, with the working shown at every step.
Open tool FreeLong Division Calculator
Divide two numbers the long way, with the full step-by-step bring-down process and the quotient plus remainder shown.
Open tool FreeFactorial Calculator
Calculate n! for any non-negative integer, with the full multiplication chain shown for small numbers and fast results for large ones.
Open toolGeometry
FreePythagorean Theorem Calculator
Find a missing side of a right triangle from the other two, using a² + b² = c², with every step of the formula shown.
Open tool FreeCircle Area Calculator
Find the area, circumference, diameter or radius of a circle from any one measurement, with the formula and steps shown.
Open tool FreeSphere Surface Area Calculator
Find the surface area, volume, radius or diameter of a sphere from any one measurement, with the formula and steps shown.
Open tool FreeMidpoint Calculator
Find the midpoint and the distance between two coordinates, with the midpoint and distance formula steps shown.
Open toolStatistics
More statistics calculators (mean, median, mode, standard deviation) are coming in a future wave.
Fractions & Basics
FreeFraction Calculator
Add, subtract, multiply, divide and simplify fractions and mixed numbers — with the answer as a reduced fraction and a decimal, plus the working.
Open tool FreeRounding Calculator
Round any number to the nearest place, decimal or significant figure, with half-up, banker's, ceiling, floor and truncate modes — and see which digit decided.
Open tool FreePercentage Calculator
Answer the three common percentage questions: what is X% of Y, X is what percent of Y, and the percent increase or decrease from one number to another.
Open tool FreePEMDAS Calculator
Solve any expression in the correct order of operations (PEMDAS / BODMAS), one step at a time, with parentheses, exponents and roots.
Open tool FreeScientific Notation Calculator
Convert any number to scientific, E- and engineering notation — or add, subtract, multiply and divide in scientific notation, with the steps explained.
Open tool FreeScientific Calculator
Trigonometry, logarithms, powers, roots, factorial, constants and memory — in degrees or radians, with full keyboard support and no sign-up.
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