Area Calculator
Calculate the area of a square, rectangle, triangle, circle, trapezoid or parallelogram.
Average Calculator
Find the mean, median, mode, range and more from a list of numbers — all at once.
Base Converter
Convert numbers between binary, octal, decimal and hexadecimal.
Circle Calculator
From the radius, diameter, circumference or area of a circle, find all the others instantly.
Combination Calculator
C(n, r) — how many ways r items can be chosen from n when order does not matter.
Exponent Calculator
Raise any number to a power instantly, including zero and negative exponents.
Factorial Calculator
Compute n! with exact results even for very large numbers.
Fraction Calculator
Add, subtract, multiply or divide two fractions — with the answer fully simplified, as a mixed number and as a decimal.
GCF & LCM Calculator
Find the greatest common factor (GCF) and least common multiple (LCM) of two or more numbers.
Golden Ratio Calculator
Split a length into two parts by the golden ratio (φ ≈ 1.618).
GPA Calculator
Calculate your GPA on the US 4.0 scale from your course credits and letter grades (A, A−, B+ …).
Grade Calculator
Turn the number of questions and how many were missed into a percentage score and letter grade (A–F).
Logarithm Calculator
Calculate the logarithm log_b(x) for any base, plus the natural log (ln), log₁₀ and log₂.
Mean, Median, Mode Calculator
Find the mean, median, mode, range, min, max, sum and count of a list of numbers.
Modular Arithmetic Calculator
Compute a mod n: the remainder, quotient and the division identity.
Percentage Calculator
Do every percentage calculation in one tool: percentage of a number, what percent, and increase/decrease.
Percent Difference Calculator
Find the percent difference between two values (relative to their average) — symmetric, with neither as the reference.
Perimeter Calculator
Calculate the perimeter of basic geometric shapes.
Permutation Calculator
P(n, r) — how many ways r items can be arranged from n when order matters.
Prime Factorization Calculator
Break an integer down into its prime factors.
Probability Calculator
Find the probability of a single event, or of two independent events happening together or either one.
Proportion Calculator
Solve the proportion a / b = c / d for the missing value — the classic rule of three.
Pythagorean Theorem Calculator
Solve a right triangle with a² + b² = c² — find the hypotenuse or a missing leg, plus area and perimeter.
Quadratic Formula Calculator
Solve any quadratic equation ax² + bx + c = 0 — real or complex roots, discriminant and vertex.
Ratio Calculator
Simplify a ratio to its lowest terms or solve a proportion for the unknown.
Root Calculator
Calculate square roots, cube roots and any nth root.
Rounding Calculator
Round any number to a set number of decimal places, significant figures, or the nearest multiple (10, 5, 0.5…).
Scientific Notation Calculator
Convert numbers between plain decimal and scientific notation (a × 10ⁿ), with the coefficient and exponent shown.
Slope Calculator
Find the slope, y-intercept, equation, angle and distance from two points on a line.
Standard Deviation Calculator
Calculate the standard deviation, mean and variance of your data set.
Volume Calculator
Calculate the volume of a cube, prism, cylinder, sphere or cone.
Z-Score Calculator
Find the z-score (standard score) of a value and its percentile on the normal distribution.