Cron packs a schedule into five fields: minute, hour, day of month, month, day of week. The syntax is compact and unforgiving; */5 and 5 mean very different things. A generator lets you build from dropdowns or paste an expression and read it back in plain English with the next runs.
What you'll learn
- Read the five fields and the *, /, - and , operators
- Build common schedules without memorising syntax
- Confirm an expression by checking its next five run times
Step by step
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Paste an expression or use the fields
Open the Cron Expression Generator. Type an expression such as */5 * * * * or set minute, hour, day, month and weekday from the selects.
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Read the explanation
The tool renders the schedule in English and lists the next run times in your local timezone, so a mistake shows up before it reaches production.
*/5 * * * * Every 5 minutes 0 9 * * 1-5 At 09:00, on Monday to Friday 0 0 1 * * At 00:00, on day 1 of the month 30 2 * * SUN At 02:30, on Sunday */15 9-17 * * 1-5 Every 15 minutes, between 09:00 and 17:59, on Monday to Friday
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Adjust with the operators
Use * for any, */n for every n, a-b for a range, and a,b,c for a list. Names like MON-FRI and JAN are accepted; 7 also means Sunday.
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Copy into crontab
Copy the expression and prepend it to the command in your crontab, CI schedule or Kubernetes CronJob.
Common problems
Minute must be between 0 and 59
A field is out of range. Minutes are 0–59, hours 0–23, days 1–31, months 1–12, weekdays 0–7.
The job runs at the wrong time
Cron uses the server's timezone. The tool shows local times for your browser; convert if the server runs in UTC.
Day of month and day of week both set
Standard cron runs when either matches, not both. 0 0 13 * 5 fires on every 13th and every Friday.
FAQ
Does it support seconds?
No. The standard five-field format has no seconds; Quartz and some cloud schedulers add a sixth field.