Unit Converter
Convert length, weight, temperature, area, volume, speed, data, time
Roman Numeral Converter
Convert between integers and Roman numerals with validation
Percentage Calculator
All percentage calculations: X% of Y, change, increase/decrease
Percentage Change Calculator
Percent increase or decrease between two values
Statistics Calculator
Mean, median, mode, range, variance, and standard deviation
Fraction Calculator
Add, subtract, multiply, and divide fractions with simplification
Ratio Calculator
Simplify ratios and solve for missing values
Permutation & Combination Calculator
Permutations and combinations with and without repetition
Quadratic Equation Calculator
Solve ax² + bx + c with real and complex roots
Logarithm Calculator
Logs with any base plus natural and common logarithms
Roman Numeral Calculator
Convert between Arabic numerals and Roman numerals
Prime Factorization Calculator
Prime factors of any number with exponent notation
Z-Score Calculator
Z-score, percentile, and tail probabilities for the normal distribution
Confidence Interval Calculator
Confidence intervals with margin of error and critical values
Sample Size Calculator
Minimum survey sample size with confidence level and error margin
Probability Calculator
Binomial probabilities and event rules for combinations of A and B
Area Calculator
Area and perimeter for rectangles, triangles, circles and more
Speed Distance Time Calculator
Solve speed, distance or time with km/h, m/s, mph and knots
LCM & GCD Calculator
Least common multiple and greatest common divisor of any set of numbers
Factorial Calculator
Exact n! for huge numbers plus digit count and scientific notation
Scientific Notation Calculator
Convert to and from scientific, E and standard notation
Temperature Converter
Celsius, Fahrenheit, Kelvin, Rankine and Réaumur conversion
Length Converter
Convert mm, cm, m, km, inches, feet, yards and miles
Weight Converter
Convert mg, g, kg, tons, ounces, pounds and stones
Volume Converter
Convert ml, liters, cups, pints, quarts and gallons
Algebra Calculator (Linear & Quadratic Solver)
Solve linear equations ax + b = c, quadratic equations ax² + bx + c = 0 with real/complex roots, and find the equation of a line through two points. Step-by-step results.
ANOVA Calculator (One-Way)
Run a one-way ANOVA on up to several groups: sums of squares, degrees of freedom, mean squares, the F-statistic and an exact p-value from the F-distribution.
Chain Rule Calculator
Apply the chain rule d/dx f(g(x)) = f'(g(x))·g'(x) to common composite functions — power, exponential, trig and log — with a step-by-step breakdown at any point x.
Circumference Calculator
Find the circumference, diameter, radius and area of any circle from a single value — radius, diameter, circumference or area. C = 2πr, A = πr².
Common Denominator Calculator
Find the least common denominator of two fractions, rewrite both as equivalent fractions, and add or subtract them with a simplified result.
Derivative Calculator
Symbolic differentiation in your browser: enter an expression in x using +, −, ×, ÷, ^, sin, cos, tan, exp, ln, sqrt and get the derivative plus its numeric value at any point.
Elimination Calculator (Solve Linear System)
Solve a 2×2 system of linear equations step by step using the elimination method. Shows the full working — scaling, subtraction, solving and back-substitution.
Exponent Calculator
Raise any base to any power: negative, fractional and large exponents. See the decimal result, scientific notation, the reciprocal form for negative powers and more.
Exponential Growth Calculator
Model exponential growth A = P(1+r)^t for populations, revenue, bacteria, inflation and more — with doubling time, growth table and projections.
Factoring Calculator
Factor quadratic expressions ax² + bx + c into (px + q)(rx + s) when possible, or express them using the roots. Step-by-step with integer and fractional factors.
Fibonacci Calculator – Nth Fibonacci Number & Sequence
Free Fibonacci calculator. Compute the nth Fibonacci number, view the full sequence, and see the golden ratio convergence instantly.
Fourier Series Calculator – Coefficients for Common Waveforms
Free Fourier series calculator. Compute a0, an and bn coefficients for square, triangle, sawtooth, half-wave and full-wave rectified signals.
Gauss-Jordan Elimination Calculator – Solve Linear Systems
Free Gauss-Jordan elimination calculator. Solve systems of linear equations, get the reduced row echelon form (RREF) and detect unique, infinite or no solutions.
Golden Ratio Calculator – Divide Any Length at φ
Free golden ratio calculator. Divide any length into golden sections (61.8% / 38.2%), see the value of φ and its powers, with a visual split bar.
HCF & LCM Calculator – Highest Common Factor & Least Common Multiple
Free HCF and LCM calculator. Find the highest common factor (GCD) and least common multiple of up to six numbers with prime factorizations shown.
Integral Calculator – Definite Integral by Trapezoidal & Simpson's Rule
Free definite integral calculator. Evaluate integrals numerically using the trapezoidal rule and Simpson's rule with step size control.
Inverse Function Calculator – Find f⁻¹(x) Numerically
Free inverse function calculator. Numerically solve x = f⁻¹(y) for any function, check monotonicity, and verify f(f⁻¹(y)) = y.
IQR Calculator – Interquartile Range & Outlier Detection
Free IQR calculator. Compute Q1, median, Q3 and the interquartile range for any dataset, with 1.5×IQR outlier detection and a box plot.
LCM Calculator – Least Common Multiple of Multiple Numbers
Free LCM calculator. Find the least common multiple of up to six numbers with prime factorization and divisibility checks.
Log Calculator – Logarithm with Any Base
Free log calculator. Compute log base 2, 10, e or any custom base, with natural log, change-of-base formula and inverse verification.
Long Division Calculator – Quotient, Remainder & Repeating Decimals
Free long division calculator. Get the quotient, remainder and decimal expansion of any integer division, with repeating digit detection and step-by-step working.
LU Factorization Calculator – Decompose a Square Matrix
Free LU factorization calculator. Decompose any square matrix into lower and upper triangular matrices (PA = LU) with partial pivoting and verification.
Matrix Calculator – Add, Subtract, Multiply, Invert & More
Free matrix calculator. Add, subtract, multiply, transpose, find determinants and inverses of up to 4×4 matrices with step-by-step results.
Mean Calculator – Arithmetic, Geometric, Harmonic & Weighted Average
Free mean calculator. Compute arithmetic, geometric, harmonic and weighted averages plus median, mode, range, variance and standard deviation of any list of numbers.
Mean Deviation Calculator – Average Absolute Deviation MAD
Free mean deviation calculator. Compute the average absolute deviation (MAD), mean squared deviation (MSD) and root mean square deviation of any dataset.
Median Calculator – Find the Middle Value of a Dataset
Free median calculator. Find the median, quartiles, min, max and range of any dataset with sorted values and step-by-step explanation.
Midpoint Calculator – Find the Midpoint Between Two Points
Free midpoint calculator. Find the midpoint between two points in 2D or 3D space with step-by-step results and distance.
Modulo Calculator – a mod b with Step-by-Step Remainder
Free modulo calculator. Compute a mod b, get the remainder with quotient, and see step-by-step work. Supports negative and large numbers.
Percentile Calculator – Find Any Percentile of a Dataset
Free percentile calculator. Find the value at any percentile (25th, 50th, 75th, 90th, 95th…) using linear interpolation with sorted data.
Pythagorean Theorem Calculator – Find a, b or c
Free Pythagorean theorem calculator. Solve for hypotenuse or any leg of a right triangle with step-by-step work, area and perimeter.
QR Factorization Calculator – Gram-Schmidt QR Decomposition
Free QR factorization calculator. Decompose any square matrix A into Q·R using the modified Gram-Schmidt process, with verification.
Quadratic Formula Calculator – Solve ax² + bx + c = 0
Free quadratic formula calculator. Solve ax² + bx + c = 0 with real and complex roots, discriminant, vertex, axis of symmetry and step-by-step work.
Quartile Calculator – Q1, Q2, Q3, IQR & Outliers
Free quartile calculator. Find Q1, Q2 (median), Q3, the interquartile range (IQR), outliers and a box plot of your data.
Rational Expressions Calculator – Simplify & Operations
Free rational expressions calculator. Simplify, add, subtract, multiply and divide rational expressions with step-by-step factoring and excluded values.
Rounding Calculator – Round to Nearest Decimal, Whole, Tenth
Free rounding calculator. Round any number to the nearest integer, tenth, hundredth, thousandth or any decimal place with step-by-step result.
Sig Fig Calculator – Significant Figures Rounding
Free significant figures calculator. Count and round to significant figures, with scientific notation, step-by-step rules and calculations that respect sig figs.
Simplex Method Calculator – Linear Programming Solver
Free simplex method calculator for linear programming. Maximize an objective function under ≤ constraints with full tableau iterations and final solution.
Slope Calculator – Slope Between Two Points & Line Equation
Free slope calculator. Find the slope between two points, the line equation y = mx + b, angle of inclination, and graph data.
Speed Calculator – Distance, Time & Speed with Units
Free speed calculator. Find speed, distance or time with any unit combination — km/h, mph, m/s, knots — and convert between them.
Square Root Calculator – Simplify & Calculate √x
Free square root calculator. Calculate the square root of any number, simplify radical form (e.g. √50 = 5√2), cube roots and nth roots.
Standard Deviation Calculator – Population & Sample SD
Free standard deviation calculator. Compute population and sample standard deviation with variance, mean, deviations and step-by-step table.
Synthetic Division Calculator – Divide Polynomials by x − c
Free synthetic division calculator. Divide any polynomial by (x − c) using the synthetic division method with quotient, remainder and step-by-step row work.
T-Test Calculator – One & Two Sample t-Test Statistics
Free t-test calculator. Run one-sample and two-sample t-tests with t-statistic, degrees of freedom and p-value estimates, plus interpretation.
Trapezoidal Rule Calculator – Numerical Integration
Free trapezoidal rule calculator. Approximate definite integrals with the trapezoid rule, Simpson's rule and the midpoint rule, with step-by-step intervals and error estimates.
Triangle Calculator – Sides, Angles, Area & More
Free triangle calculator. Enter three side lengths to get area, all angles, height, perimeter, circumradius, inradius and triangle type with an instant visual.
Shapes Area Calculator
Find the area of 9 common shapes instantly. Rectangle, triangle, circle, trapezoid, hexagon, ellipse, and more, with results in square feet, meters, and acres.
Random Number Generator
Generate cryptographically secure random integers in any range — unique, sorted or with repeats, live sum and average stats, one-click copy and export.
Number to Words Converter
Spell out any number in English — integers, decimals and negatives up to 10^63, with currency and ordinal modes plus British