Math tools

Splits restaurant bills from subtotal, tip %, tax and party size. Use when dining out or splitting; differs from vat-gst by gratuity split vs tax-inclusive pricing. Returns tip amount, total and per-person share. 100% client-side.

Scientific calculator with trig and logs. Use for advanced math; for datasets use statistics-calculator. Input: expression. Returns result. 100% client-side, files never leave browser.

Compute mean, median and stddev. Use for datasets; for single expressions use scientific-calculator. Input: numbers ≤10MB. Returns stats. 100% client-side, files never leave browser.

Calculate sale price after discount. Use for percent off; for change percent use percentage-change-calculator. Input: price + percent. Returns final price. 100% client-side, files never leave browser.

Add, subtract, multiply, and divide fractions with exact rational arithmetic — no floating-point drift. Simplifies automatically.

Simplify ratios, split a total in a given ratio, and solve proportions a:b = c:x.

Greatest common divisor and least common multiple of two or more numbers via Euclid's algorithm.

Descriptive statistics for a list of numbers: mean, median, mode, range, variance, standard deviation.

Solve ax² + bx + c = 0, including complex conjugate roots.

Calculate percentage increase, decrease, difference, and relative change between two values.

Compute nCr (combinations) and nPr (permutations) with exact integer arithmetic. Supports large n via logarithms.

Calculate z-score (standard score) from raw value, mean, and standard deviation. Supports p-value lookup.