Cron daily at 22:45: the expression, explained, in Docker
The cron expression for “daily at 22:45” is 45 22 * * *. This page shows what each field does, the next five times it will fire, the mistake most people make with it, and a working Docker example you can paste.
The expression
45 22 * * *
| Field | Value | Meaning |
|---|---|---|
| minute | 45 | exactly 45 |
| hour | 22 | exactly 22 |
| day of month | * | every day of month |
| month | * | every month |
| day of week | * | every day of week |
Next five runs (UTC, from now)
- 2026-09-18 22:45 UTC
- 2026-09-19 22:45 UTC
- 2026-09-20 22:45 UTC
- 2026-09-21 22:45 UTC
- 2026-09-22 22:45 UTC
Mistakes people make with this schedule
- 22:45 in which timezone? A server in UTC fires an hour or two off in Berlin depending on the season. Set the job timezone explicitly.
- Assuming the server clock is your clock. Cron runs in the machine’s timezone unless the runtime says otherwise; the examples here are UTC.
- No lock around a job that might overlap itself, and no alert when it silently stops. That second one is what Supercrontab is for.
Run it in your stack
# Dockerfile RUN apk add --no-cache curl RUN echo '45 22 * * * curl -fsS http://app:3000/cron/run' > /etc/crontabs/root CMD ["crond", "-f", "-l", "2"]
Or skip the sidecar: expose the route and let Supercrontab call it.
Questions
Does 45 22 * * * run in my local time?
Only if the scheduler is configured for it. crontab uses the system timezone; Vercel and GitHub Actions always use UTC; Laravel and node-cron take a timezone option. In Supercrontab the timezone is a field on the job.
What if the previous run is still going?
Classic cron starts the next run anyway. Add a lock (flock on Linux, withoutOverlapping() in Laravel) or let Supercrontab skip the tick while the previous request is open.
Is there a shorter way to write this?
No. The five-field form is the shortest portable version.