Math & calculators
Percentage calculator (all cases)X% of Y, X is what % of Y, percentage change, and increase/decrease by %.Expression calculatorEvaluate expressions with + − × ÷ ^ ( ), sqrt, sin, cos, tan, log, ln, pi and e — safely, without eval.Fractions: simplify & decimalSimplify a fraction, convert to decimal and percentage, or a decimal to a fraction.GCD & LCMFor any list of integers.Prime check & factorisationIs it prime? Its prime factors and divisors.Number base converterBinary, octal, decimal, hexadecimal and any base 2–36.Roman numerals converterNumbers ⇄ Roman numerals (1–3999).Statistics: mean, median, mode, SDDescriptive statistics for a list of numbers.GPA calculator (4.0 scale)Weighted GPA from grades and credit hours.