Useful numbers.
Nothing in the way.

Arithora helps with the calculations that turn up in everyday life, from splitting dinner to measuring a room.

The answer should make sense

Every tool explains its formula, shows an example, and describes its assumptions. Inputs update results immediately, and the calculation logic has automated tests for reference examples and boundary cases.

Small tools, clear boundaries

Calculators use JavaScript number arithmetic, with exact BigInt arithmetic for integer fractions and base conversions. Display precision and limitations are explained on each page. Estimates cannot account for every real-world condition, and rounded displays may not add up exactly.

For a purchase, payment, construction project, or other consequential decision, check the inputs and confirm the result against the relevant source or professional guidance. Arithora provides calculation tools, not financial, legal, or professional advice.

Your inputs stay with you

Calculations run in your browser. No account is required, and calculator inputs are not sent to a server or saved in browser storage.