📐 Statistics & Probability 16
Binomial Distribution CalculatorBinomial probabilities: P(X=k), cumulative, mean, variance.Combination CalculatorCompute combinations C(n, r).Confidence Interval CalculatorConfidence interval for a population mean.Linear Regression CalculatorLeast-squares line of best fit for (x, y) data: slope, intercept, R².Margin of Error CalculatorMargin of error for survey or poll given sample size and confidence.Mean Median Mode CalculatorFind the mean, median, mode, and range of a list of numbers.Normal Distribution CalculatorCumulative and tail probabilities for the standard normal distribution.Percentile CalculatorFind any percentile of a dataset.Permutation CalculatorCompute permutations P(n, r).Probability CalculatorP(A and B), P(A or B), and conditional probability.Quartile / IQR CalculatorQuartiles, IQR, and outliers using Tukey fences.Range CalculatorFind the range (max - min) of a dataset.Sample Size CalculatorRequired sample size for survey margin of error and confidence.Standard Deviation CalculatorCompute sample or population standard deviation.Variance CalculatorCompute sample or population variance.Z-Score CalculatorCompute the z-score of a value relative to mean and SD.
📐 Financial Math 12
APR CalculatorSolve for the implied annual percentage rate (APR) of a loan.CAGR CalculatorCompound annual growth rate between two values over a period.Compound Interest CalculatorSee how a starting amount grows with compound interest.Credit Card Payoff CalculatorSee how long it will take to pay off a credit card balance at a fixed monthly payment.Inflation CalculatorSee how inflation grows future costs and erodes today’s buying power.Investment Growth CalculatorProject the future value of an investment from a starting balance and monthly contributions.Loan CalculatorEstimate the monthly payment and total interest on a fixed-rate loan.Markup / Margin CalculatorMarkup, margin, and profit from cost and selling price.Mortgage CalculatorEstimate a monthly mortgage payment including principal, interest, taxes and insurance.Retirement CalculatorProject a retirement nest egg from current savings, contributions, return, and years.ROI CalculatorCalculate return on investment (ROI) and annualized return.Savings Goal CalculatorFind how much to save each month to hit a savings goal by a target date.
📏 Conversions 11
Area ConverterConvert between square meters, feet, acres, hectares and other area units.Binary / Hex / Decimal ConverterConvert between binary, octal, decimal, and hexadecimal.Data Storage ConverterConvert between bits, bytes, KB, MB, GB, TB and PB in binary or decimal.Energy ConverterConvert between joules, calories, watt-hours, BTU and other energy units.Length ConverterConvert between metric and imperial length units.Mass & Weight ConverterConvert between grams, kilograms, pounds, ounces, stones and tons.Pressure ConverterConvert between pascals, bar, atmospheres, psi, mmHg and other pressure units.Speed ConverterConvert between m/s, km/h, mph, ft/s, knots and Mach.Temperature ConverterConvert between Fahrenheit, Celsius and Kelvin.Time ConverterConvert between milliseconds, seconds, minutes, hours, days, weeks, months and years.Volume ConverterConvert between liters, milliliters, gallons, cups, fluid ounces and other volume units.
📐 Specialty & Other Tools 10
Age CalculatorCalculate an exact age from a birthdate in years, months and days.Calendar CalculatorCount days until or since a target date.Date CalculatorAdd or subtract days, weeks, months or years from a date.Day of the Week CalculatorFind what day of the week any date falls on.Discount CalculatorSee the sale price and how much you save.Interest Rate ConverterConvert between APR and APY for any compounding frequency.Tax CalculatorAdd sales tax to any amount and see the total.Time Duration CalculatorCalculate the exact span between two dates.Tip CalculatorCalculate the tip and split the bill in one tap.Unit Price CalculatorCompare two package sizes and see which is cheaper per unit.
📐 Geometry 10
Circle CalculatorFind radius, diameter, circumference, and area of a circle.Cone CalculatorVolume, slant height, and surface area of a cone.Cube CalculatorEdge, volume, surface area, and diagonals of a cube.Cylinder CalculatorVolume, lateral area, and surface area of a cylinder.Polygon CalculatorArea, perimeter, apothem, and angles of any regular polygon.Rectangle CalculatorArea, perimeter, and diagonal of a rectangle.Sphere CalculatorRadius, diameter, volume, and surface area of a sphere.Square CalculatorArea, perimeter, and diagonal of a square.Trapezoid CalculatorArea and perimeter of a trapezoid.Triangle CalculatorArea, perimeter, angles, and type of a triangle from three sides.
📐 Trigonometry 8
Angle ConverterConvert between degrees, radians, gradians, revolutions, arcminutes, and arcseconds.Inverse Trig CalculatorCompute arcsine, arccosine, and arctangent in degrees or radians.Law of Cosines CalculatorSolve a triangle from two sides + included angle, or three sides.Law of Sines CalculatorFind a missing side or angle in any triangle using the Law of Sines.Pythagorean Theorem CalculatorFind the missing side of a right triangle using a^2 + b^2 = c^2.Right Triangle CalculatorSolve a right triangle from any two of: leg a, leg b, hypotenuse c, or angle A.Trig CalculatorCalculate sin, cos, tan, csc, sec, cot for any angle.Unit Circle CalculatorFind (cos, sin) on the unit circle, all six trig functions, and quadrant.
📐 Matrices & Vectors 8
Cross Product CalculatorCross product of two 3D vectors plus angle.Dot Product CalculatorDot product of two vectors plus angle between.Matrix Determinant CalculatorDeterminant of 2x2 and 3x3 matrices.Matrix Inverse CalculatorInverse of 2x2 and 3x3 matrices via adjugate method.Matrix Multiplication CalculatorMultiply two matrices A and B.Matrix Transpose CalculatorTranspose a matrix — rows become columns.Vector Magnitude CalculatorCompute vector magnitude and unit vector.Vector Projection CalculatorProject vector a onto vector b.
📐 Algebra 8
Distance Formula CalculatorFind the distance between two points using the distance formula.Linear Equation CalculatorSolve ax + b = c for x.Logarithm CalculatorCompute logarithms in any base.Midpoint CalculatorFind the midpoint between two points.Quadratic Formula CalculatorSolve any quadratic equation ax^2 + bx + c = 0 with real or complex roots.Slope CalculatorFind the slope, y-intercept, and equation of a line through two points.Slope-Intercept Form CalculatorFind the y = mx + b form of a line through two points.System of Equations CalculatorSolve a 2x2 system of linear equations.
📐 School / Homework 8
Long Division CalculatorDivide with quotient, remainder, and decimal result.Long Multiplication CalculatorMultiply with partial-product breakdown.Number to Words ConverterConvert a whole number into English words.Order of Operations CalculatorEvaluate an arithmetic expression using PEMDAS / BODMAS.Percent Decrease CalculatorCalculate the percent drop from an original value to a lower new value.Percent Increase CalculatorCalculate the percent change between two values.Roman Numeral ConverterConvert between decimal numbers and Roman numerals.Significant Figures CalculatorCount significant figures and round to a target precision.
📐 Basic 5
Basic CalculatorAdd, subtract, multiply, divide, raise to a power, or take a modulo.Decimal CalculatorConvert a decimal to a reduced fraction, mixed number or percent.Mixed Number CalculatorAdd, subtract, multiply or divide mixed numbers.Root CalculatorFind the nth root of any number.Scientific CalculatorApply scientific functions.
📊 Number Theory 5
Factor CalculatorList all positive factors of a whole number.GCF CalculatorFind the greatest common factor of two or three whole numbers.LCM CalculatorFind the least common multiple of two or three whole numbers.Prime Factorization CalculatorBreak a whole number into its prime building blocks.Prime Number CalculatorCheck whether a whole number is prime.
📐 Complex Numbers 4
Complex Conjugate CalculatorConjugate of z = a + bi with key identities.Complex Modulus & Argument CalculatorModulus, argument, and polar form of a complex number.Complex Number CalculatorAdd, subtract, multiply, divide complex numbers; modulus and conjugate.Polar / Rectangular Form ConverterConvert complex numbers between rectangular and polar forms.
➗ Fractions & Ratios 4
Fraction CalculatorAdd, subtract, multiply, or divide two fractions and get the answer simplified, as a mixed number, and as a decimal.Fraction to Decimal ConverterConvert a decimal to a simplified fraction, or turn any fraction into a decimal and percentage.Proportion CalculatorSolve a proportion A : B = C : x for the missing value.Ratio Calculator (Simplifier)Reduce a ratio to its simplest whole-number form, with two or three terms.
🔢 Arithmetic & Percentages 3
Average Calculator (Mean, Median, Mode)Paste a list of numbers and get the mean, median, mode, range, sum, and count instantly.Percentage CalculatorThree percentage tools in one: find a percentage of a number, work out what percent one number is of another, and measure a percentage increase or decrease.Rounding CalculatorRound any number to a set number of decimal places, or to the nearest 10, 100, or 1000.
🧮 Powers & Roots 3
Exponent Calculator (Power)Raise any number to any power, including negative and fractional exponents.Scientific Notation ConverterConvert numbers to scientific notation and back, with the coefficient and exponent shown.Square Root CalculatorFind the square root, cube root, or any nth root of a number.