Math
Everyday and advanced math: fractions, ratios, primes, statistics, roman numerals, equations and more.
Annulus Area Calculator
Calculate the area of an annulus, the ring between two concentric circles, from its outer and inner radius. Returns both circumferences and width too. Free.
Area Calculator
Find the area of a circle, square, rectangle, triangle, trapezoid, parallelogram, ellipse, sector or rhombus. Free and runs in your browser.
Arithmetic Sequence Calculator
Find the nth term, the sum of n terms and the full term list for any arithmetic or geometric sequence. Enter the first term, step or ratio, and n.
Average Calculator
Find the mean, median, mode, range, sum, count, min and max of a list of numbers. Paste values separated by commas, spaces or new lines.
Benford's Law Calculator
Analyze any data set for Benford's Law conformity. Paste numbers to get the first-digit distribution, chi-square test, MAD score and per-digit z-stats.
Big Number Calculator
Add, subtract, multiply, divide, power, modulo, factorial, GCD and LCM on integers of any length. Exact results with no rounding, computed in your browser.
Binary Calculator
Add, subtract, multiply and divide binary numbers. See decimal, octal and hex results, two's complement and step-by-step working. Free and private.
Birthday Paradox Calculator
Calculate the probability that two people in a group share a birthday. See why just 23 people gives better than even odds, for any group size.
Boolean Algebra Simplifier
Simplify boolean expressions to minimal SOP and POS forms. Enter an expression or minterms with don't cares to get prime implicants and the answer.
Circle Calculator
Enter any one circle property and get the radius, diameter, circumference and area instantly. Free, accurate and runs in your browser.
Coefficient of Variation Calculator
Calculate the coefficient of variation (CV), the standard deviation divided by the mean, as a ratio and a percentage. Sample or population. Free and private.
Coin Flip
Flip a virtual coin online and get heads or tails instantly. Flip one or many at once, watch the animation, and track a running heads vs tails tally.
Coin Flip Probability Calculator
Calculate the probability of getting a number of heads in coin flips. Supports fair or biased coins and exactly, at least, or at most a target.
Complex Number Calculator
Add, subtract, multiply and divide complex numbers. Get the modulus, argument, conjugate and polar form of a + bi instantly. Free and private.
Cone Volume Calculator
Calculate the volume and surface area of a cone from its radius and height. Returns slant height, lateral area and total area. Free, accurate and instant.
Confidence Interval Calculator
Calculate a confidence interval for a mean or proportion. Enter your sample stats and confidence level to get the interval, margin of error, and critical value.
Correlation Coefficient Calculator
Calculate the Pearson correlation coefficient r and r squared from two data sets. Paste paired x,y values to measure linear association. Free and private.
Covariance Calculator
Calculate sample and population covariance between two data sets. Paste paired x,y values to see how two variables vary together. Free and private.
Cylinder Volume Calculator
Calculate the volume and surface area of a cylinder from its radius and height. Returns lateral area, total area and base area too. Free and instant.
Decimal to Fraction
Convert any decimal to a fraction online. Get the simplified fraction and the mixed number instantly, with negatives and whole numbers supported.
Descriptive Statistics Calculator
Get a full descriptive statistics summary from a list of numbers: mean, median, mode, variance, standard deviation, quartiles and the interquartile range.
Dice Probability Calculator
Calculate the probability of rolling a target sum with any number of dice. Choose exactly, at least, or at most, and see the odds as a percentage.
Dice Roller
Roll dice online with standard RPG notation like 2d6+3, d20 or 4d8-1. Quick-pick d4 to d100, see every die and the total, with a roll history. Free.
Distance Between Two Points Calculator
Find the distance between two points with the distance formula. Get the length, midpoint and slope of the segment, computed live with full precision.
Distance Formula Calculator
Find the distance, midpoint and slope between two points. Enter two sets of x and y coordinates to get the straight-line distance and line details.
Ellipse Area Calculator
Find the area, circumference and eccentricity of an ellipse from its semi major and semi minor axes. Uses the Ramanujan perimeter formula. Free and instant.
Expected Value Calculator
Calculate the expected value of a discrete distribution. Enter each outcome's probability and value to get the probability-weighted average instantly.
Exponent Calculator
Raise any base to any power online. Handles negative and fractional exponents, shows the result with scientific notation, and updates instantly.
Factorial Calculator
Calculate the factorial of any non-negative integer with exact big-number precision. Get n! instantly, even for large values, then copy the result. Free.
Fibonacci Calculator
Find the nth Fibonacci number with full precision, list the sequence up to n, and see the golden ratio approximation. Exact results for large n using BigInt.
Final Grade Calculator
Find the score you need on your final exam to reach a target grade. Enter your current grade, your goal and how much the final is worth.
Fraction Calculator
Add, subtract, multiply or divide two fractions and get a fully simplified answer, the decimal value and the mixed number form. Free and instant.
Fraction to Decimal
Convert any fraction to a decimal instantly. Enter a numerator and denominator to see the exact value and whether the decimal terminates or repeats.
Frustum Volume Calculator
Calculate the volume and surface area of a conical frustum, a truncated cone, from its top radius, bottom radius and height. Returns slant height too. Free.
GCD and LCM Calculator
Find the greatest common divisor and least common multiple of a list of integers. Enter two or more numbers separated by commas or spaces.
GCD Calculator
Find the greatest common divisor of two or more integers with the Euclidean algorithm. Handles negatives and zero. Free, fast, and private.
Geometric Mean Calculator
Calculate the geometric mean of any data set online, the right average for growth rates, ratios and returns. Paste your numbers for instant results. Free.
Golden Ratio Calculator
Split any length by the golden ratio (phi, 1.618). Enter the whole, the longer or the shorter segment and get the matching golden proportions instantly.
GPA Calculator
Calculate your weighted GPA on the 4.0 scale. Add each course with its letter grade and credit hours to get your grade point average instantly.
Harmonic Mean Calculator
Calculate the harmonic mean of any data set online, the right average for rates and speeds. Paste your numbers for instant, accurate results. Free and private.
Hexagon Calculator
Calculate the area, perimeter, apothem and diagonals of a regular hexagon from its side length. Exact formulas give precise results. Free and private.
Interquartile Range Calculator
Calculate Q1, the median, Q3 and the IQR of your data, plus Tukey outlier fences. Spots outliers automatically. Free, private and runs in your browser.
Law of Cosines Calculator
Solve any triangle with the law of cosines. Enter two sides and the included angle (SAS) or all three sides (SSS) to find every side, angle and the area.
Law of Sines Calculator
Solve a triangle with the law of sines. Enter a known angle and its opposite side plus one more angle or side to find the remaining angles and sides.
LCM and GCD Calculator
Find the GCD (greatest common divisor) and LCM (least common multiple) of two or more integers instantly. Enter a list of numbers and get both. Free.
LCM Calculator
Find the least common multiple of two or more positive integers. Folds the GCD-based formula across your list. Free, accurate, and private.
Letter Grade Calculator
Convert a percentage to a letter grade and 4.0 GPA points. Enter a score from 0 to 100 to see the letter, from A plus down to F, and its grade points.
Linear Equation System Solver
Solve a system of linear equations with 2 or 3 unknowns. Enter the coefficients and constants to get x, y and z, or detect no or infinite solutions.
Linear Regression Calculator
Fit a least squares line to your x and y data. Get the slope, intercept, equation, r-squared, and correlation, plus a scatter plot, in your browser.
Log Calculator
Calculate the logarithm of a number to any base, plus ln, log base 10 and log base 2. Enter a value and base for instant, accurate results.
Lottery Odds Calculator
Calculate the odds of winning any pick-k-of-n lottery, with optional bonus ball. See the jackpot odds and the chance of matching fewer numbers.
Magic Square Generator
Generate a magic square of any order, solve a partly filled one, or check if a grid is magic. Odd, singly even and doubly even methods, in your browser.
Margin of Error Calculator
Calculate a survey margin of error from sample size, proportion and confidence level. Includes a finite-population correction. Free and private.
Matrix Calculator
Add, subtract, multiply, transpose, and invert matrices online. Find determinants and scale by a scalar with editable grids and instant results.
Maze Generator
Generate a random maze of any size with five classic algorithms, then solve the shortest path and export it as ASCII art. Seeded and reproducible.
Mean Median Mode Calculator
Calculate the mean, median, mode and range of any data set online. Paste a list of numbers for instant central tendency results. Free, private and accurate.
Midrange Calculator
Calculate the midrange of a data set online: the average of the lowest and highest value. Also shows the min, max and range. Free, private and instant.
Modular Exponentiation Calculator
Compute base^exponent mod m with big integers, fast. Also find modular inverses and the GCD. Negative exponents supported when the base is invertible.
Modulo Calculator
Compute the modulo, remainder, and quotient of any two numbers, including negatives. See how the % operator and floored modulo differ. Free tool.
Number Base Converter
Convert numbers between any base from 2 to 36, including binary, octal, decimal and hex. Handles huge numbers exactly with arbitrary precision. Free, private.
Number to Words
Convert numbers to written words instantly. Spell out whole numbers or write a cheque amount in dollars and cents, then copy the result. Free and private.
Odds Converter
Convert betting odds between decimal, fractional and American formats and see the implied probability. Enter any one format to get them all. Free tool.
Ordinal Number Converter
Turn any number into its ordinal form, like 1st, 22nd or 113th, and spell it out as words such as twenty-first. Free, instant and private.
Outlier Calculator
Find outliers in your data using the Tukey IQR fence method. Paste numbers to see the fences, the flagged outliers and a cleaned data set. Free and private.
Parallelogram Area Calculator
Calculate the area and perimeter of a parallelogram from base and height, or from two sides and the angle between them. Exact results, no signup. Free.
Parlay Calculator
Calculate combined parlay odds and payout from decimal odds. Enter each leg and your stake to see total return, profit, and implied probability.
Percent Error Calculator
Calculate percent error between a measured and accepted value, plus percent difference between two values. Clear steps for labs. Free and private.
Percentage Change Calculator
Calculate the percent increase or decrease between two numbers. Also find what percent X is of Y and work out P percent of any number. Free and instant.
Percentile Calculator
Find the value at any percentile and the percentile rank of a value in your data set. Uses linear interpolation, the spreadsheet standard. Free and private.
Permutation and Combination Calculator
Calculate permutations (nPr) and combinations (nCr) for choosing r items from n. See both results with the formulas and factorials, updated live.
Polygon Area Calculator
Find the area of a regular polygon from its sides and side length, or any polygon from its vertex coordinates with the shoelace formula. Free and instant.
Polygon Diagonals Calculator
Count the diagonals of any polygon and find its interior angle sum, each interior angle and the exterior angle from the number of sides. Free and instant.
Polynomial Calculator
Add, subtract, multiply, differentiate and integrate polynomials, evaluate them at a value and read the degree. Enter coefficients and get a clean result.
Prime Factorization Calculator
Break any whole number into its prime factors. Get the factorization in exponent form like 2^3 x 3^2 x 5, a factor table, and whether the number is prime.
Prime Number Checker
Check if a number is prime and see its full prime factorization and all divisors. Enter any whole number and get an instant answer.
Probability Distribution Calculator
Compute binomial, normal, and Poisson probabilities. Get PMF or PDF, cumulative CDF, plus mean and variance, updated live as you type.
Proportion Calculator
Solve a proportion a/b = c/d for the missing value. Leave one box blank and get the answer by cross multiplication, instantly and free. No signup needed.
Pyramid Volume Calculator
Calculate the volume and surface area of a square pyramid from its base edge and height. Returns slant height, lateral and base area too. Free and instant.
Pythagorean Theorem Calculator
Find the missing side of a right triangle with a squared plus b squared equals c squared. Get the legs, hypotenuse, area and perimeter instantly.
Quadratic Equation Solver
Solve any quadratic equation ax^2 + bx + c = 0. Enter the coefficients to get the real or complex roots, the discriminant and the vertex.
Ratio Calculator
Solve a proportion A:B = C:D by leaving one value blank, or reduce any ratio to its lowest terms. Free, instant, and runs in your browser.
Ratio Simplifier
Simplify a ratio to its lowest terms and scale it up or down. Reduce 1920:1080 to 16:9, see the decimal value, and multiply both sides by any factor.
Rectangular Prism Calculator
Calculate the volume, surface area and space diagonal of a rectangular prism or box from its length, width and height. Exact formulas, instant results. Free.
Regular Polygon Calculator
Find the area, perimeter, interior and exterior angles, apothem and circumradius of a regular polygon from its sides and side length. Free and instant.
Right Triangle Calculator
Solve a right triangle from any two values: two legs, a leg and the hypotenuse, or a side and an angle. Get sides, angles, area and perimeter.
Roman Numeral Converter
Convert numbers to Roman numerals and Roman numerals to numbers. Type a number from 1 to 3999 or a Roman numeral and copy the result. Free and private.
Rounding Calculator
Round a number to decimal places or the nearest 5, 10, or 0.25. Choose half up, bankers, ceiling, floor, or truncation. Handles negatives. Free.
Scientific Notation Calculator
Convert numbers to and from scientific notation and E notation. Get the mantissa, exponent, and standard form, with negatives and zero handled.
Scientific Notation Converter
Convert numbers to and from scientific notation and E notation. Enter a number or a value like 1.23 x 10^4 to see the standard decimal form. Free and private.
Sector Area Calculator
Calculate the area, arc length and chord of a circular sector from its radius and central angle. Works in degrees or radians. Free and instant.
Set Calculator
Calculate the union, intersection, difference, and symmetric difference of two sets. Check subset and disjoint relationships. Free and instant.
Significant Figures Calculator
Count the significant figures in any number and round to a set number of sig figs. See which digits count and why, with scientific notation. Free and private.
Significant Figures Calculator
Count significant figures in a number and round to any number of sig figs. Handles leading and trailing zeros with a clear rounding result. Free.
Slope Calculator
Find the slope, y-intercept, line equation, distance, midpoint and angle from two points. Enter two coordinates and read every value instantly.
Special Right Triangle Calculator
Find every side of a 45-45-90 or 30-60-90 triangle from one known side. Uses the fixed ratios to return all sides, the area and the perimeter instantly.
Sphere Volume Calculator
Calculate the volume and surface area of a sphere from its radius. Also returns diameter and great-circle circumference. Free, accurate and instant.
Standard Deviation Calculator
Calculate standard deviation and variance online. Paste a list of numbers to get the mean, count, and both sample and population results instantly.
Sudoku Solver
Solve any Sudoku puzzle instantly and generate new ones. Type the grid, get the unique solution, see candidates and clue counts. Runs in your browser.
T-Test Calculator
Run a one sample, two sample or paired t-test. Paste your data or enter summary stats to get the t statistic, exact p-value, df, and confidence interval.
Test Grade Calculator
Grade any test fast. Enter the number of questions and how many are wrong to get the percent score, letter grade and a full EZ grader chart.
Tetrahedron Calculator
Calculate the volume, surface area, height and face area of a regular tetrahedron from its edge length. Uses exact formulas for precise results. Free to use.
Torus Volume Calculator
Calculate the volume and surface area of a torus, a donut shape, from its major radius and minor radius. Uses exact formulas and returns precise results. Free.
Trapezoid Area Calculator
Calculate the area of a trapezoid from its two parallel sides and height. Optionally find the perimeter from all four sides. Free, accurate and instant.
Triangle Area Calculator
Find the area of a triangle from base and height, three sides (Heron's formula) or two sides and an angle (SAS). Free, accurate and instant.
Triangle Calculator
Find a triangle's area from base and height or from three sides with Heron's formula, and solve right triangles with the Pythagorean theorem.
Trig Functions Calculator
Calculate sin, cos, tan, csc, sec and cot for any angle in degrees or radians. Undefined functions, like tan at 90 degrees, are clearly flagged.
Truth Table Generator
Generate a truth table from any boolean expression. Supports AND, OR, NOT, XOR, NAND, NOR, XNOR, IMPLIES and IFF. Runs in your browser.
Variance Calculator
Calculate population and sample variance online, with the matching standard deviations and mean. Paste a list of numbers for instant results. Free and private.
Vector Calculator
Add, subtract, scale, and find the dot and cross product of 2D and 3D vectors. Get magnitude, unit vector, angle, distance, and projection instantly.
Volume Calculator
Find the volume of a cube, box, sphere, cylinder, cone, pyramid, ellipsoid or capsule. Enter the dimensions and get the volume and surface area instantly.
Weighted Average Calculator
Calculate a weighted average from value and weight pairs. Enter each value with its weight to get the weighted mean, total weight and weighted sum.
Z-Score Calculator
Calculate a z-score from a value, mean, and standard deviation. See the percentile and two-tailed p-value, with a plain-English reading of the result.