Everyday tools

Splitting a bill, checking a discount, figuring out how much overtime is actually worth, working out your exact age for a form. The small calculations that come up most weeks, not once a year.

Percentage calculatorWhat is X% of Y, X is what % of Y, and percent change→ Time calculatorAdd up hours and minutes, shift lengths, decimal hours for payroll→ Dice rollerd4 to d100, cryptographically fair - the method stated, not hidden→ Time calculatorAdd and subtract h:m:s, plus decimal hours for timesheets→ Dice rollerd4 to d100, RPG notation, cryptographically fair→ Money toolsLoan calculator with real offset modeling, staged savings growth→ Age calculatorExact age in years, months, and days - calendar-aware→ Date calculatorDays between two dates, adding or subtracting, or counting down. Shows both counting conventions, since 1 to 2 January is either one day or two→ Pregnancy due date calculatorLMP, ultrasound, conception, or IVF - the honest range, not a fake-precise single day→ Chinese zodiac & age calculatorThe real Lunar New Year date for your birth year, not a Gregorian-year guess→ Gold weight & value calculatorTola, sovereign, gram - the real value at your purity, and the GST breakdown most bills get wrong→ BMI & daily calorie calculatorCDC categories plus the clinically validated Mifflin-St Jeor formula→ Unit price comparatorWhich pack is actually the better deal→ Trip fuel cost calculatorMulti-leg road trip fuel cost, split among riders→ Power, energy & time calculatorAppliance running cost, EV charge time, and more→ Pace, speed, distance & time calculatorWhat pace do you need? Real race distances built in→ Flow rate, volume & time calculatorHow long will this pool or tank actually take to fill?→ Wind chill & heat index calculatorWhat does it actually feel like outside?→ Fuel economy comparatorMPG, L/100km, km/L - all at once, plus which car is cheaper→ Pressure converter (tire pressure + ground pressure)psi, bar, kPa - plus a ground pressure calculator→ Torque spec converterNm on the manual, ft-lb on the wrench - with real fastener presets→ Data transfer time calculatorWhy your "100 Mbps" connection isn’t 100 MB/s→