Math Calculators
Percentage and other everyday math tools, calculated instantly.
About these calculators
Sixty-nine calculators covering the arithmetic students actually get stuck on and the operations professionals actually repeat: percentage conversions in four directions, fraction simplification step by step, triangle geometry with the law of sines and cosines, prime factorisation showing every division, and statistical means beyond the simple average — geometric, harmonic and weighted.
The tools favour transparency over black boxes. Long division shows its working; significant figures explain rounding rules; quadratic formula displays the discriminant so you can see why roots turn complex. Where conventions differ — degrees versus radians, scientific versus engineering notation — the calculator says which convention it applies rather than leaving you to guess.
Choosing the right calculator
Schoolwork and exams
Percentage, fraction and ratio tools handle the bulk of school arithmetic; gcf-lcm and prime-factorisation cover number theory chapters; pythagorean-theorem, right-triangle and the trigonometry family (sine through arctan) serve geometry units. Every result includes enough intermediate steps to copy the method, not just the answer.
Everyday practical maths
Discount and percentage-change calculations for shopping comparisons, GPA and grade for academic tracking, golf-handicap for the course, and big-number for the occasional need to multiply numbers too large for a phone's default calculator — precision held via arbitrary-precision arithmetic.
Technical work
Matrix operations, logarithm and exponent tools, scientific notation and summation support coursework and quick engineering checks. Roman-numeral conversion and number-sequence identification fill specialist niches without pretending to be full computer-algebra systems.
Math calculators we stand behind
Percentage Calculator
Calculate percentages, percentage difference and percentage change instantly. Work out what 20% of any number is, find discounts, markups and more.
Rounding Calculator
Round any number to the nearest value, or up and down, to any decimal places. Also round to the nearest multiple.
Standard Form Calculator
Convert numbers to and from standard form (scientific notation) with one click — large and small numbers made easy.
Proportion Calculator
Solve a:b = c:d for any missing value and check cross-products in seconds — for recipes, ratios and maps.
Also available (65) — work in progress, not yet indexed
These calculators work but are still being checked for accuracy and sourcing, so they are not in search yet. They are free to use.