cron expression · plain english
Run a cron job every Monday morning
Fires at 09:00 every Monday — start-of-week trigger. Used for weekly reports, sprint kickoff jobs, and Monday-only newsletter sends.
beginner
POSIX / Jenkins / Quartz / AWS
0 9 * * 1
run a cron job every monday morning.
Next 5 fire times
Computed live in your local timezone. The cron expression itself is timezone-agnostic — these times reflect your browser clock.
Cross-system syntax variants
Same intent, different schedulers. Use this table when migrating between systems.
| System | Expression | Note |
|---|---|---|
| Standard cron (POSIX) | 0 9 * * 1 | day-of-week 1 = Monday on Linux/macOS (some systems use 0=Sunday=Mon=1, others 0=Sunday with 1=Monday) |
| Cron (named days) | 0 9 * * MON | POSIX cron supports MON/TUE/WED... — clearer than numbers |
| Jenkins | H 9 * * 1 | or H 9 * * MON |
| Quartz (Java) | 0 0 9 ? * MON | Quartz uses MON/TUE; ? for day-of-month when day-of-week is set |
| systemd timer | OnCalendar=Mon 09:00 | human-readable form |
| AWS EventBridge | cron(0 9 ? * MON *) | AWS Quartz-flavored — ? is required when DOW is specified |
Common pitfalls
- WARNING: cron's day-of-week numbering is inconsistent across systems. POSIX uses 0-6 with both 0 and 7 = Sunday; Quartz uses 1-7 with 1=Sunday. Always test or use named days.
- Cron does NOT understand 'business Monday' — the Monday after a Sunday holiday still fires at 09:00. Add a holiday-skip layer in code.
- DST handover Sundays don't affect Monday timing, but if your cadence is `0 1 * * 1` and DST falls back, you get two fires.
Use cases
- Weekly status report
- Sprint planning notification
- Monday newsletter blast
- Past-week metrics rollup
Translate any cron expression
cronwtf takes any cron string and returns plain-English description plus the next 5 fire times in your timezone. Standard 5-field, Jenkins H, Quartz 6-field — all supported.
Open cronwtf
Related cron schedules
cron during business hours only (9-5, weekdays) · cron every night at 3 am · cron: every hour (top of hour) · cron every friday at 5 pm (end of work week) · ↗ timezone-aware weekly meetings