Everyday Calculators
The everyday calculators don't fit neatly into health or finance but come up constantly: days until (or since) a date, someone's exact age, a fair tip and split, what a sale price actually saves, and converting a number between units — length, weight, temperature, and more.
Date arithmetic is a common source of small errors — leap years, varying month lengths, time zone boundaries — so these calculators are built and tested against exactly those edge cases, and every result shows the formula and numbers behind it.
- Date Difference CalculatorHow many days lie between two dates? This calculator counts them in whole days, converts the total into weeks and into approximate months and years, and reports separately how many of those days fall Monday to Friday.Shows its formula1 figures checked · 2026-08-12
- Age CalculatorHow old is someone on a given day, counted the way an official form counts it? This calculator answers in completed years, months and days, and adds the total number of days lived and the date of the next birthday.Shows its formula
- Unit ConverterConverts length, weight, area, volume, and temperature between metric and customary units, using exact defined factors.Shows its formula
- Tip CalculatorWork out what a table owes once the tip is on top. Give the bill, the percentage and the headcount, and the calculator returns the tip, the total and each share, with the option to round up either the total or the individual amounts.Shows its formula
- Discount CalculatorTwo discounts stacked on one item are not the sum of the two percentages. Put in the original price and both offers to see the final price, the amount saved, and the effective rate the stack really works out to.Shows its formula
- Korea Paid Annual Leave CalculatorKorean paid leave runs on two separate tracks, and which one governs your year depends on how long you have been employed. This tool works out where you stand on any date you pick.Shows its formula3 figures checked · 2026-08-12
- Korea Weekly Holiday Pay CalculatorKorean law pays for one rest day a week on top of the hours you actually work. This works out what that allowance adds to your pay at your hourly rate.Shows its formula4 figures checked · 2026-08-19
- Split Bill CalculatorWho owes what when one bill covers a table? Give the total, the headcount, and how many people are paying nothing or half, and the calculator returns each share plus the surplus that rounding up quietly collects.Shows its formula