Date & Time Tools — 8 tools

Date Difference

Calculate the number of days between two dates.

days between duration

Unix Timestamp

Convert between Unix timestamps and human dates.

epoch unix convert

Day of the Week

Find the weekday for any date (Zeller algorithm).

weekday calendar date

Age Calculator

Calculate age in years, months, and days.

birthday age born

Time Zone Converter

Convert a time between world time zones.

timezone utc convert

Countdown Timer

Countdown to a specific date and time.

countdown until deadline

ISO Week Number

Find the ISO week number for a date.

week iso year

Julian Date

Convert between calendar dates and Julian Day Numbers.

julian astronomical jd