9 calculators
Date & Time calculators
Ages, durations, and countdowns.
- 1Age Calculator
Calculate exact age in years, months, and days between two dates, plus days to the next birthday.
- 2Date Difference Calculator
Days, weeks, and months between two dates.
- 3Add/Subtract Days Calculator
Add or subtract days from a date.
- 4Countdown Calculator
Days remaining until a target date.
- 5Duration Calculator
Total time from hours, minutes, seconds.
- 6Business Days Calculator
Count Mon–Fri days between two dates (inclusive).
- 7ISO Week Number Calculator
ISO 8601 week number for any date.
- 8Timezone Offset Calculator
Convert clock time between UTC offsets.
- 9Sleep Time Calculator
Bedtimes that finish on 90-minute cycles before wake-up.