Date calculator

Find how far apart two dates are — total days, weeks, a calendar breakdown and business days — or add and subtract intervals from a date. All math is in UTC.

Find how far apart two dates are — total days, weeks, a calendar breakdown and business days — or add and subtract intervals from a date. All math is in UTC.

How to use

  1. On the Difference tab, pick two dates
  2. Read total days, weeks, business days and the Y/M/D breakdown
  3. On the Add/Subtract tab, pick a base date, amount and unit
  4. See the resulting date and weekday

Frequently asked questions

What counts as a business day?

Monday through Friday. The count excludes the start date and skips weekends.

Why UTC?

Using UTC avoids off-by-one errors from daylight-saving-time transitions between the two dates.

How is the calendar breakdown computed?

As whole years, months and days, borrowing across month boundaries — so it reads like «1y 2m 5d».