Cron Expression Builder & Tester
Build standard five-field Unix cron expressions, understand their schedule, and preview the next five matching times in an IANA time zone.
Your data stays in your browser. No sign-in required.
Build a schedule
Standard five-field Unix cron. No seconds, year, command text or Quartz fields.
Minute · Hour · Day of month · Month · Day of week
Visual builder
Schedule preview
Every 5 minutes
Next five expected runs
Calculating in your browser…
Actual execution depends on your server’s configured time zone and scheduler. Missing DST times are skipped here; repeated times appear twice with different offsets. This tool does not schedule or run jobs.
How to use this tool
- Choose a preset, select a visual schedule, or type a five-field expression.
- Use the field editors for lists, ranges, steps, weekdays, day of month and month. Manual input and visual fields stay synchronized.
- Select the server’s intended time zone and review the explanation and next five expected runs. Copy the expression into your scheduler separately.
Privacy
Your entries and files are processed on your device. They are not uploaded, added to this page’s URL, saved in browser storage, or included in analytics. Reset clears this tool’s working state.
Frequently asked questions
Which cron syntax is supported?
Five fields in minute, hour, day-of-month, month, day-of-week order. Supports numbers, *, comma lists, ascending ranges, */step, range/step, and three-letter month or weekday names. Sunday is 0 or 7. Quartz extensions, seconds, years, macros and command text are not supported.
How are day fields and DST handled?
When both day fields are restricted, either may match (Unix OR behavior). A wildcard day field uses AND behavior. Missing local times are skipped; repeated times are listed twice with their offsets. Your scheduler may apply a different DST policy.
Does this run or schedule a job?
No. It only calculates matching instants in your browser, searching up to 28 years ahead. Actual execution depends on your server’s time zone, scheduler and availability.