Cron Explainer & Builder

Parse and build cron expressions. Supports standard (5-field) and Spring Boot / Quartz (6-field with seconds).

Enter a cron expression above. Auto-detects standard vs Spring format.
STANDARD (crontab, GitHub Actions, most CI/CD)
┌──── minute (0-59)
│ ┌──── hour (0-23)
│ │ ┌──── day of month (1-31)
│ │ │ ┌──── month (1-12)
│ │ │ │ ┌──── day of week (0-6, Sun=0)
* * * * *
SPRING BOOT / QUARTZ (6 fields, has seconds)
┌──── second (0-59)
│ ┌──── minute (0-59)
│ │ ┌──── hour (0-23)
│ │ │ ┌──── day of month (1-31)
│ │ │ │ ┌──── month (1-12)
│ │ │ │ │ ┌──── day of week (0-6, Sun=0)
0 * * * * *
* any   , list   - range   / step   ? no specific value (Spring only)
Spring ? is used in day-of-month or day-of-week when the other field is set. Auto-detected by field count.
curl "swissarmydev.tools/cron?expr=*/5+*+*+*+*" curl "swissarmydev.tools/cron?expr=0+*/30+*+*+*+*" # Spring 6-field