Cron Expression Generator
Build and explain cron expressions.
LocalYour data is processed locally in your browser and is not uploaded to Alphzen.
Explain an expression to see the next run times.
How to use
- Pick a preset, or type a 5-field expression (minute hour day-of-month month day-of-week).
- Six fields are treated as seconds plus the Unix five.
- Read the field summary and the next few run times (local timezone).
- Copy the expression into crontab, CI, or a scheduler that uses Unix cron.
Features
- Parses *, lists, ranges, and steps, plus month and weekday names.
- Accepts ? as a synonym for * (common in some schedulers).
- Shows upcoming fire times using your browser timezone.
- Does not implement Quartz’s L, W, or # specifiers — those are called out as unsupported.
- Local processing only.
Examples
30 9 * * 1-5
at 09:30, on 1-5, every month (local time).
FAQ
Is this Quartz or Unix cron?
Unix-style by default (5 fields). A 6th leading field is seconds. Quartz special characters such as L, W, and # are not implemented.
Sunday is 0 or 7?
Both 0 and 7 mean Sunday, matching common crontab behaviour.
Why don’t next runs match production?
Schedulers may use UTC, skip DST repeats, or use Quartz rules. Treat next runs as a local preview, then confirm on the system that will execute the job.
Related guides
Related tools
About this tool
A cron expression is a compact schedule. The Unix five fields are minute, hour, day of month, month, and day of week. Misreading a field is a common outage.
Alphzen explains the expression and estimates the next fires in the timezone your browser uses. That is a preview, not a guarantee from systemd, Kubernetes, or GitHub Actions.
For a single instant rather than a schedule, use the Unix Timestamp Converter.