Add Business Hours to a Date
Answers "if I start now and burn N working hours, when am I done?" — useful for SLA targets, ticket due dates, or planning effort that has to fit between 09:00 and 17:00 with weekends and holidays subtracted. Configurable work window, working-day toggles (Mon–Fri default, change for Sun-start cultures or 6-day weeks), and a free-form holiday list. The breakdown lists each working day touched and how many hours were consumed there.
| Day | Hours used |
|---|---|
| 2026-08-21 | 8.00 h |
| 2026-08-24 | 8.00 h |
Holidays are an explicit list — country calendars vary, so paste yours. Sub-day starts that fall mid-window are honored exactly.
How to use
- Set the start datetime (defaults to now) and the work hours to add.
- Configure your work window (default 9–17), toggle weekends, and paste any holidays as `YYYY-MM-DD` per line.
- Result is the landing timestamp; the breakdown below shows the per-day split.
Frequently asked questions
- What if the start is outside the work window?
- It rolls forward to the next working day's start. Adding 1 h to Saturday at 03:00 with a Mon–Fri 9–17 window lands at Monday 10:00.
- Does it handle partial hours?
- Yes — the hours field accepts decimals (e.g. 2.5). Day-end overflow rolls cleanly to the next working day with the remaining fraction.
- Which time zone does the work window apply in?
- The same one the start time is read in, so nine-to-five means the local nine-to-five. When a clock crosses zones — a customer in one, the team in another — decide first whose working day the commitment is measured in, because the same number of hours lands on a different timestamp depending on the answer.
- What happens if the daylight-saving change falls inside the span?
- A working day here is defined by clock times, not by elapsed hours, so a day that shifts still runs 09:00 to 17:00 on the clock even though it lasts 23 or 25 real hours. That is normally what an office-hours commitment means. If yours is written in elapsed time instead, calculate it as a duration rather than as business hours.
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