Everyday Math Calculators
Quick answers for everyday math — percentages, unit conversions, and stats.
Number of Calculators: 40
What to Know
The broadest category on the site by calculator count, covering everything from a quick Percentage or Tip calculation to genuine statistics (Confidence Interval, P-Value, Sample Size, Least-Squares Regression) and pure math tools (Matrix, Quadratic Formula, Logarithm, Modulo). If you learned it in a math class, there's a decent chance it's here.
A few calculators solve for whichever value you don't already know rather than one fixed direction — Circle, Distance & Slope, and Triangle all work this way, so you enter whatever you actually have and get the rest. Random Number and Dice Roller are the two calculators here that deliberately don't produce a reproducible, shareable result, since generating something new is the whole point.
- PercentageFind what a percent of a number is, what percent one number is of another, the reverse percentage, or the change and difference between two values.
- TipCalculate the tip amount, total bill, and per-person split for any bill, with optional tax and rounding.
- DiscountFind the sale price, amount saved, or original price for a percent-off, fixed-amount, or reverse discount, with optional stacking and sales tax.
- UnitConvert between length, weight, volume, temperature, area, speed, time, digital storage, pressure, energy, power, and angle units instantly.
- Grade Point Average (GPA)Calculate your weighted or unweighted GPA from a list of course grades and credit hours, fold in a previous cumulative GPA, or find the GPA you need this term to hit a target.
- FractionAdd, subtract, multiply, or divide two fractions (including mixed numbers), or convert a decimal to its simplest fraction.
- GradeFind the minimum score you need on a final exam to reach your target overall grade.
- Sales TaxAdd sales tax to a price, or work backward from a tax-included total to find the price before tax.
- StatisticsCalculate the mean, median, mode, range, variance, and standard deviation of any list of numbers.
- Random Number GeneratorGenerate one or more random whole numbers within a range, with or without repeats.
- TriangleFind a triangle's area, perimeter, and all three angles from its three side lengths, plus whether it's equilateral, isosceles, or scalene, and acute, right, or obtuse.
- AreaCalculate the area (and perimeter or circumference) of a rectangle, square, circle, triangle, or trapezoid.
- VolumeCalculate the volume and surface area of a rectangular prism, cube, sphere, cylinder, or cone.
- Quadratic FormulaSolve any quadratic equation of the form ax² + bx + c = 0, including complex roots.
- Square Root / Nth RootFind the square root, cube root, or any nth root of a number, including real roots of negative numbers.
- MatrixAdd, subtract, multiply, transpose, or find the determinant of a matrix of any size, with a resizable grid input.
- Greatest Common Factor and Least Common MultipleFind the Greatest Common Factor (GCF) and Least Common Multiple (LCM) of two or more whole numbers.
- RatioSimplify a ratio to its lowest terms, or solve a proportion for its missing fourth term.
- RoundingRound a number to a set number of decimal places, significant figures, or the nearest multiple.
- ProbabilityFind the probability of a single event, or the combined probability of two independent events.
- Long DivisionDivide two whole numbers and see the quotient, remainder, decimal result, and the full step-by-step long division process.
- Z-ScoreFind a value's z-score and percentile within a normal distribution, given the distribution's mean and standard deviation.
- CircleFind a circle's radius, diameter, circumference, and area — enter any one of them and this calculator solves for the other three.
- Distance, Midpoint & SlopeFind the distance, midpoint, and slope between two coordinate points on a graph.
- Percent ErrorFind the percent error between an experimental (measured) value and a theoretical (accepted) value.
- Confidence IntervalFind the confidence interval for a population mean, given a sample's mean, standard deviation, and size.
- Sample SizeFind how many respondents or observations a survey needs to estimate a proportion within a chosen margin of error and confidence level.
- P-ValueFind the p-value for a given z-score in a one-tailed or two-tailed hypothesis test, and whether it is statistically significant.
- Prime FactorizationBreak a whole number down into its prime factors, and find out whether it is itself a prime number.
- Roman NumeralConvert a number to a Roman numeral, or a Roman numeral back to a number.
- Scientific CalculatorA full scientific calculator with trig functions, logarithms, exponents, factorial, and parentheses.
- Basic CalculatorA simple everyday calculator for addition, subtraction, multiplication, and division.
- Permutation and CombinationFind the number of permutations (nPr) and combinations (nCr) for choosing r items from a total of n.
- Scientific NotationConvert a standard number to scientific notation, or a scientific notation coefficient and exponent back to a standard number.
- Dice RollerRoll any number of dice with any number of sides, plus an optional modifier — see the total and every individual roll.
- LogarithmFind the logarithm of a number in any base, also shown as log base 10, natural log (ln), and log base 2.
- ExponentRaise a number to any power -- a positive, negative, or fractional exponent -- and get the exact result.
- ModuloFind the remainder left over when one number is divided by another (a mod n), including negative numbers.
- Least Squares RegressionFit a straight line through a set of data points, and find the slope, intercept, and correlation strength.
- Linear InterpolationEstimate a value between two known data points, assuming a straight-line relationship between them.