Every 5 minutes
- Thu, Nov 5, 03:40:00 PMin 3 min
- Thu, Nov 5, 03:45:00 PMin 8 min
- Thu, Nov 5, 03:50:00 PMin 13 min
- Thu, Nov 5, 03:55:00 PMin 18 min
- Thu, Nov 5, 04:00:00 PMin 23 min
What is a cron expression?
Cron is the classic Unix scheduler. A cron expression is a line of five (sometimes six or seven) space-separated fields that describes when a job runs: minute, hour, day of month, month and day of week, plus optional seconds and year. So 0 9 * * 1-5 means every weekday at 09:00.
Worked example: 0 9 * * 1-5 runs every weekday at 09:00. Field by field — minute 0 fires at the top of the hour; hour 9 means 09:00; day of month * means every day; month * means every month; day of week 1-5 means Monday through Friday. Implementations with seconds add a sixth leading field (0 0 9 * * 1-5), or you can use a shortcut such as @daily.
How to use the cron explainer
- Type or paste a cron expression — 5, 6 or 7 fields, or a shortcut such as @daily.
- Read the plain-language description to confirm what the schedule means.
- Check the field breakdown to see exactly how each position was interpreted.
- Review the next run times (or the @reboot note) before deploying the job.
Frequently asked questions about cron
What do the five cron fields mean?
Left to right: minute (0-59), hour (0-23), day of month (1-31), month (1-12) and day of week (0-7, where both 0 and 7 are Sunday). An asterisk means every value.
Is the schedule in my local timezone?
Expressions carry no timezone: they are interpreted in the timezone of the machine running the cron daemon. Containers usually run in UTC, so check TZ before you deploy.
How do the @ shortcuts work?
A shortcut replaces the whole expression: @hourly, @daily (midnight), @weekly, @monthly and @yearly, plus @reboot, which runs once at daemon start and therefore has no next run time.