Math and Statistics

Math and Statistics calculators cover the numbers you meet in school, work, and research — averages and percentages, square roots, standard deviation and normal distributions, number-base conversions, and more. Frequently used tools include the Average Calculator, Percentage Deviation Calculator, Square Root Calculator, Normal Distribution Calculator, and 2's Complement Calculator.

Pick a tool below to get an instant answer, or open the Trending tab to see what other people are calculating this week. Everything is free and works on any device.

  • Percentage Deviation Calculator
    Calculate percentage deviation easily with input for expected and actual values. Determine the variance between predicted and real outcomes for accurate analysis and decision-making.
  • Square Root Calculator
    Enter a number to calculate its square root (√x) instantly. See the principal root in seconds for quick checks, homework, or everyday math.
  • Average Calculator
    Enter numbers separated by commas to get the average, sum, count, median, geometric mean, minimum, maximum, and range—instant results.
  • Normal Distribution Calculator
    Calculate normal distribution probabilities with this easy-to-use Normal Distribution Calculator. Input mean, standard deviation, and X value to instantly determine probabilities and percentiles for any normal distribution.
  • 2x2 Eigenvalue Calculator
    Find the eigenvalues of any 2x2 matrix instantly. Computes trace, determinant, discriminant, and real or complex eigenvalues with full steps.
  • Double-Exponential (DE) Quadrature: Integral over (-∞, ∞)
    Numerically integrate any f(x) over the whole real line (-∞, ∞) using Double-Exponential (tanh-sinh / Takahasi-Mori) quadrature. Set precision in significant digits.
  • Sum of First N Natural Numbers Calculator
    Calculate the sum of the first N natural numbers (1+2+3+...+n) instantly using the formula Sn = n(n+1)/2. Free, fast, and accurate.
  • Reverse Percentage Calculator
    Find the original price before a discount or increase. Enter the final price and the percentage to reverse-calculate the starting value instantly.
  • Percent Change Calculator
    Calculate percent change from original and new values. See increase or decrease, the difference, and absolute percent change in seconds.
  • Percentage Increase Calculator
    Find the percent increase between two numbers in seconds. Enter the original and new value to get the exact growth percentage with the formula. Try it free.
  • Random Number Generator (1 to 100)
    Free random number generator from 1 to 100. Click Pick for a uniform random integer (each number 1% likely), with a running pick counter and Reset.
  • Percent Grade to Degrees Calculator
    Convert a percent grade (slope) into degrees instantly. Enter the grade % to get the slope angle in degrees and radians using arctangent.
  • Hex Calculator
    Enter two hexadecimal numbers, choose add, subtract, multiply, or divide, and see the result instantly in hex for quick, accurate calculations.
  • Hex to Decimal Converter
    Enter a hexadecimal number to get its decimal value and see the binary equivalent. Fast hex-to-decimal conversion for math, coding, and data tasks.
  • Fisher's Exact Test Calculator (2x2)
    Compute the exact p-value for a 2x2 contingency table using Fisher exact test. Get the hypergeometric probability and two-sided p-value instantly.
  • Variance Calculator
    Calculate variance easily with this online tool. Enter comma-separated numbers to determine the spread of data points from the mean. Ideal for statistical analysis and data interpretation.
  • Poisson Distribution Calculator
    Compute the Poisson distribution: probability mass f(x;lambda), lower cumulative P(X<=x), and upper cumulative Q(X>=x) tabulated over a sequence of x values.
  • Numerical Integration over (a, b) — Double-Exponential (Tanh-Sinh) Method
    Compute the definite integral of f(x) on a finite interval [a, b] with Double-Exponential (Tanh-Sinh) quadrature — robust even for endpoint singularities like 1/sqrt(x).
  • Standard Deviation Calculator
    Calculate sample standard deviation from comma-separated numbers, and get mean, variance, median, min, max, count, and sum in seconds.
  • Factor Calculator
    Calculate factors of any number with this Factor Calculator. Find all divisors quickly and easily for mathematical analysis, problem-solving, and understanding number properties.
  • Semi-Infinite Interval Integration by Double-Exponential (DE) Formula
    Compute the integral of f(x) over [a, infinity) using Double-Exponential (DE) quadrature for algebraically-decaying integrands. Universal numerical method.
  • Stem and Leaf Plot Generator
    Free stem-and-leaf plot generator. Paste your numbers to build a stem-and-leaf diagram with single or split stems, plus mean, median, mode and standard deviation.
  • Prime Number Primality Checker
    Check if a number is prime or composite. Lists all factors, the previous prime and next prime using a fast trial-division primality test.
  • Studentized Range Distribution Probability Calculator
    Compute the lower and upper cumulative probability of the studentized range distribution (Tukey q statistic) for a quantile q, sample size r, df nu and c groups.

Frequently asked questions

What can I calculate with these math and statistics tools?

Everyday and academic math: means, medians and other averages, percentages and percent change, powers and roots, standard deviation and variance, probability and distributions, and base conversions such as binary or two's complement.

Do the calculators show the steps or formula?

Most show the formula and the worked result so you can follow the method, not just the final number — useful for checking homework or understanding the calculation.

Are they free and do they work on mobile?

Yes to both — free, no sign-up, and fully responsive on phones and tablets.

How accurate are the results?

They use standard mathematical formulas and are tested against known values. For high-precision or academic work, verify rounding and significant figures against your own requirements.

Which math calculators are most popular?

The list is ordered by how often each tool is used, so the most popular appear first. The Trending, Recently added, and Last updated tabs highlight what's new and rising.

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