Cron Dialects
Every cron-flavored scheduler started with Unix crontab and went its own direction. Six dialects power most production scheduling; each has its own field count, special characters, and gotchas.
Unix cron
5 fields
Standard 5-field cron used by crontab, GitHub Actions, and most CI/CD platforms.
Quartz Scheduler
7 fields · seconds · year
Java's Quartz Scheduler — 6 or 7 fields, seconds-precision, Sunday=1.
Kubernetes CronJob
5 fields
Kubernetes CronJob spec.schedule — standard 5-field, UTC by default.
AWS EventBridge
6 fields · year
AWS EventBridge / CloudWatch Events — 6 fields including year, Sunday=1, UTC only.
Spring @Scheduled
6 fields · seconds
Spring Framework — 6-field with seconds, Sunday=0 or 7, supports L for last day.
GitHub Actions
5 fields
GitHub Actions `on.schedule.cron` — standard 5-field Unix, UTC, minimum 5-minute granularity.
Want to see how a single schedule looks in each dialect? Try the multi-dialect converter — paste an expression and see the equivalent for every scheduler.