Calculate exact age in years, months, and days from a date of birth.

Count business days between two dates, excluding weekends.

Calculate how many days are left until a future date.

Add or subtract years, months, weeks, and days from a date.

Calculate the number of days, weeks, months, and years between two dates.

Calculate the duration between two times, with an optional break deduction.

Find the day of the week for any selected date.

Generate recurring dates by days, weeks, months, or years.

Generate evenly spaced time slots between a start and end time.

Convert Unix timestamps to readable UTC/local dates and convert dates back to Unix time.

Common time-unit relationships and practical notes for date/time calculations.