Working days until a deadline: calendar days vs sleeps vs business days
"How long until the deadline?" gets three different honest answers depending on whether you mean nights, every calendar day, or days the office is actually open. Mixing them up is how project plans slip by a week.
Three clocks, one deadline
| Question | What it counts | Tool |
|---|---|---|
| How many sleeps? | Midnights until the date | Countdown |
| How many calendar days? | Same number as sleeps | Countdown / date difference |
| How many weekdays vs weekend days? | Mon–Fri vs Sat–Sun split of those mornings | Countdown |
| How many working / business days? | Mon–Fri minus bank / public holidays | Bank holidays + /v1/workdays |
Example: a Friday deadline that is 10 calendar days away might be only 6 or 7 working days once weekends (and a midweek holiday) are removed — or still 10 sleeps for a child counting nights.
Weekdays from the countdown
Open countdown, set your deadline (or "next Friday" / "end of month"), and read weekdays and weekend days. Those two add up to sleeps. They do not subtract bank holidays; a Christmas Day on a Thursday still counts as a "weekday" morning in that split.
Subtract bank holidays
- List the holidays that fall inside the window with Bank Holidays (UK nations, Ireland, US, Germany nationwide or Bundesland, France, Netherlands).
- Or call the API:
# Business days in a half-open range (see docs for exact bounds)
curl -s 'https://api.oddlathe.com/v1/workdays?region=eng&from=2026-11-07&to=2026-12-25'
# Same idea for Bayern
curl -s 'https://api.oddlathe.com/v1/workdays?region=de-by&from=2026-11-07&to=2026-12-25'
Year-wide ballpark: how many working days in the UK, Arbeitstage in Germany, Ontario ESA holidays 2026 (252 working days). UK substitute Mondays matter in December — see substitute days.
Inclusive vs exclusive deadlines
Contracts disagree on whether the deadline day itself is "in". Countdown's inclusive days count both ends the way some event calendars do; sleeps stop at the morning of the target. Ship-by language ("must arrive by Friday") is usually exclusive of Saturday. When a timer looks one day short, read why countdown timers are a day off.
Related
Countdown · Bank holidays calculator · UK working days · German Arbeitstage · Ontario public holidays 2026 · Civic Holiday in Ontario · Sleeps until Christmas · Countdown timers a day off · Date difference · Anvil /v1/workdays
Questions
What is the difference between working days and weekdays?
Weekdays are Monday–Friday. Working / business days are weekdays minus public holidays for the relevant region.
Does the countdown subtract bank holidays?
No. It splits sleeps into weekdays vs weekend days. Use Bank Holidays or Anvil /v1/workdays to exclude holidays.
How do I count business days until a deadline in code?
Call https://api.oddlathe.com/v1/workdays with region, from and to. No API key.
Are sleeps the same as working days?
No. Sleeps count every midnight, including weekends and holidays. Working days skip those.
Does a UK Boxing Day Monday count?
Yes for England and Wales working-day maths — substitute days are observed bank holidays. See the substitute-days guide.
Published · updated .