Numbers & Math

Compose translate / rotate / scale / skew into a single 3×3 matrix.

Add, subtract, dot, normalize and angle-between two 2D vectors.

Determinant, inverse, product and eigenvalues of 2×2 matrices.

Compute the eigenvalues of a 2×2 matrix (real or complex).

Compute dot and cross product of two 3D vectors.

Compute the volume and surface area of spheres, cylinders, cones, cubes, boxes, pyramids and tori.

Solve Ax = b for a 3×3 system using Gauss-Jordan elimination.

Two-proportion z-test for A/B test conversions.

Calculate age in seconds, minutes, hours, days and years.

Convert nominal annual percentage rate to effective annual yield.

Calculate proportional width or height from any aspect ratio.

American Wire Gauge diameter, area, resistance and ampacity.

Update a prior probability with sensitivity and false-positive rate.

Arbitrary-precision integer and decimal calculator: add, sub, mul, div, mod, pow, gcd, lcm, factorial.

PMF, CDF, mean and variance for binomial and Poisson distributions.

Calculate AND, OR, XOR, NOT and shifts with binary and hexadecimal output.

European option pricing with Greeks.

Compute Body Mass Index and basal metabolic rate (Mifflin-St Jeor).

Reduce a Boolean expression with Quine-McCluskey.

Chi-square goodness-of-fit between observed and expected counts.

Derive diameter, circumference, area from radius — plus arc, sector and chord.

Standardised mean difference (small/medium/large effect).

Generate the Collatz (3n+1) sequence, step count and peak value.

Compute nCr, nPr and related combinatorics values.

Solve P₁V₁/T₁ = P₂V₂/T₂ for any one missing quantity.

Add, subtract, multiply, divide complex numbers.

Calculate final balance, interest earned and contributions over time.

Compute a normal-CI around the mean of a numeric sample.

Expand any number into its continued fraction [a₀; a₁, a₂, …].

Compute the 2D convex hull of a set of points (monotone chain).

Solve ax³ + bx² + cx + d = 0 — three real or one real and two complex roots.

Convert a decimal to improper / mixed fraction and detect repeating decimals.

Compute the DFT of a real signal — magnitude and phase for every frequency bin.

Plot any single-variable expression in x as an inline SVG with axes and zero crossings.

Compute expected value, variance and standard deviation from outcomes and probabilities.

Compute exact factorials and arbitrary-precision integer expressions.

Generate Fibonacci numbers with index and comma-separated output.

Evaluate Γ(x) and B(a, b) for real arguments.

Greatest common divisor and least common multiple of any list of integers.

Convert between binary and reflected Gray code in either direction.

Project the amount remaining after exponential decay, plus decay constant and mean lifetime.

Encode 4 data bits into a Hamming(7,4) codeword, or decode 7 bits and fix a single-bit error.

Solve PV = nRT for pressure, volume, moles or temperature.

Bit-level view of a number in FP16, BF16, FP32 or FP64.

What is $X today worth in N years at i% inflation? (and vice versa)

Minimize a Boolean function from minterms using a 2/3/4-variable K-map.

Solve the constant-acceleration SUVAT equations from any three of s, u, v, a, t.

Given two points, get distance, midpoint, slope and line equation.

Ordinary least-squares slope, intercept and R² for any (x, y) list.

Compute monthly payments, total interest and amortisation for a loan.

Convert log_a(x) into log_b(x) using change-of-base.

Generate magic squares for odd, doubly-even and singly-even orders.

Non-parametric two-sample rank test.

Compute the steady-state probability vector of a row-stochastic matrix via power iteration.

Evaluate mathematical expressions with functions and constants.

Add, subtract and multiply 2x2 matrices, plus determinant values.

Modular exponentiation, modular inverse, gcd, lcm.

Find solution molarity from moles (or mass + molar mass) and volume.

PDF, CDF, inverse CDF and Z-score for a normal distribution.

Net present value and internal rate of return from a cash-flow stream.

Convert between binary, octal, decimal and hexadecimal.

Integrate f(x) over [a,b] with trapezoidal or Simpson's rule.

Numerically solve a first-order ODE dy/dx = f(x, y) with the classic RK4 method.

Solve V, I, R, P from any two known values.

Generate Pascal's triangle for a chosen number of rows.

Five percentage modes: of, is what %, % change, increase, decrease.

Convert between [H⁺], [OH⁻], pH and pOH for an aqueous solution.

Convert between a photon's wavelength, frequency and energy (λf = c, E = hf).

Find the plane equation Ax + By + Cz + D = 0 from three 3D points.

Fit a polynomial to (x, y) data via least squares. Reports coefficients, R² and residuals.

Fit a polynomial through N points using Lagrange or Newton form.

Multiply two polynomials given by coefficient lists.

Check primality, factorize and list primes up to N.

Compute flight time, range, peak height and impact speed for a launched projectile.

Solve a : b = c : x by cross-multiplication.

Convert CSS px, rem and em values with configurable base font size.

List primitive Pythagorean triples (a, b, c) with c ≤ N.

Solve ax² + bx + c = 0 with real or complex roots.

Quaternion arithmetic and axis-angle conversions.

Generate cryptographically-random integers in a range.

Simulate a 1-D random walk and report the path, final position and range.

Interior angle, perimeter, area, apothem of a regular n-gon.

Decode resistor color bands to resistance + tolerance.

Convert between Roman numerals and Arabic numbers.

Find roots of f(x) = 0 using bisection or Newton's method.

Estimate take-home pay after tax, social contributions and deductions.

How many respondents do you need for a given margin of error?

Convert decimal numbers to and from scientific notation.

Union, intersection, difference and symmetric difference of two newline lists.

Visualize the sieve of Eratosthenes up to N with crossed-out composites.

Round a number to a chosen number of significant figures (decimal + scientific).

Find a simple pendulum's period and frequency from its length (or vice-versa).

Maximise an objective subject to ≤ constraints — 2-variable LP via vertex enumeration.

Compute the refraction angle and critical angle from refractive indices.

Solve the dilution equation C₁V₁ = C₂V₂ for any missing value.

Mean, median, mode, standard deviation and more for any list of numbers.

Solve 1/f = 1/do + 1/di and the magnification for a thin lens.

Calculate the tip and split a bill between any number of people.

Solve a triangle from SSS, SAS or ASA inputs.

Boolean expression with A,B,C and &, |, !, ^, ->, <-> → truth table.

Inspect a number at any bit width with sign-extend toggle.

Convert between length, mass, volume, area, speed, time and temperature.

Add or remove VAT and see net, tax and gross amounts.

Generate a 2- or 3-set Venn diagram from element lists.

Compute mean, weighted mean, median, quartiles, percentiles and standard deviation from a list of numbers.

Compare two samples' means with Welch's unequal-variance t-test.

View the first hundreds of digits of π, e or the golden ratio φ.