🔢 Math Tools

Calculate mean, median, mode, range, variance and standard deviation from a list of numbers, with the sample and population distinction handled explicitly.

Add, subtract, multiply and divide fractions, simplify them, and convert between improper fractions, mixed numbers and decimals.

A full scientific calculator with trigonometry, logarithms, powers, roots and constants, running entirely in your browser with a visible expression history.

Calculate your grade point average from course letter grades and credit hours, with weighted and unweighted options and school-specific caveats.

Work out your weighted class grade and find the score you need on the final exam to reach a target, including when that target is out of reach.

Check whether a number is prime and see its prime factorisation and divisors, with the reason only square roots need testing.

Solve quadratic equations accurately, including the cases where the textbook formula silently loses precision and returns a badly wrong root.

Solve a triangle from any three parts, showing both answers where two sides and a non-included angle admit two valid triangles.

Rate, work, mixture, age and distance problems with the equation shown — and the tempting wrong answer named beside the right one.

Equations, inequalities and systems with the working shown — including the sign flips and the systems that have no solution at all.

Drill the exact trig values — √3/2, not 0.866 — with the whole circle held exactly, because a computer cannot check it by evaluating.

Antiderivatives proved by differentiating them back — and an honest refusal where none exists, which for most functions is the true answer.

Evaluate limits with L’Hôpital’s rule and two independent probe sequences — which is how it catches the limits that look convergent and are not.

Differentiate any expression exactly, with the step-by-step rules — and see why the numerical shortcut has an accuracy floor it cannot beat.

Practice factoring, difference of squares and completing the square — including the quadratics that do not factor, which most of them do not.

Practice base conversion, modulo, modular inverses and two’s complement — including the cases where the % operator gives a different answer.

Plot any function of x, with the line broken at poles instead of drawn across them, and a warning when the curve turns faster than it can be sampled.

Check or compute the last digit of a card number, ISBN, EAN or UPC — and see exactly which typing mistakes each scheme can and cannot catch.

Calculate combinations and permutations for counting problems, with a clear test for which one your problem actually needs.

Convert between binary, decimal, hex and octal and perform bitwise operations, with two's complement handling and the shift behaviour that catches people out.

Add, multiply, transpose and find the determinant and inverse of matrices, with the dimension rules and why some matrices have no inverse at all.

Build a truth table for any expression and simplify it — with the simplified form checked against the original row by row before it is shown.

Divide polynomials long-hand or synthetically, find rational roots and differentiate — with the division identity shown holding on every result.

Slope, all three forms, intercepts, parallels and perpendiculars from two points — handling vertical lines properly instead of printing infinity.

Fits five curves to your points and shows both R-squared values — the one a spreadsheet reports and the one measured in your own units.

IQR fences by all four standard quartile conventions, z-scores with the ceiling they cannot pass, and normalisation that says when it would divide by zero.

Finds every arithmetic, geometric, polynomial and recurrence rule that fits your terms — then builds a rule giving any next term you name.

Union, intersection, difference and complement, every Venn region counted — and set identities proved over all membership patterns, not just your data.

Printable maths worksheets by grade and topic, randomised every time, with the answer key on its own page.

Everything about any number up to a billion — prime factorisation, divisors, binary, Roman numerals, and the properties that make some numbers unusual.