Cron Expression Generator
Build and validate a cron schedule, see it in plain English, and preview the next run times. Fully offline.
Open Cron Expression Generator →What is the Cron Expression Generator?
A free, private tool for building and reading standard five-field cron schedules — minute, hour, day-of-month, month and day-of-week. Type an expression or use the presets and per-field boxes to assemble one, then see exactly what it means in plain English and a preview of the next five run times. Every field is validated for ranges, steps and lists, so malformed input is flagged straight away. It runs entirely in your browser using ordinary date maths and no libraries, so nothing you enter ever leaves your device and it works fully offline.
How to use Cron Expression Generator
- Enter an expression — Type a five-field cron expression such as */5 * * * * into the top box, or pick a ready-made preset like ‘Every day at 09:00’.
- Or build it by field — Fill the minute, hour, day, month and weekday boxes and the expression is assembled for you as you type.
- Read the plain English — The description panel explains what the schedule actually does, so you can confirm it before using it.
- Check the next runs — The preview lists the next five times the schedule would fire in your local time zone, computed on the spot.
- Copy it out — Press Copy to place the finished expression on your clipboard, ready for your crontab or scheduler.
Frequently asked questions
Which cron syntax does it support?
The classic five-field format used by Unix cron: minute, hour, day-of-month, month and day-of-week. Each field accepts *, */n steps, a-b ranges and comma-separated lists.
How are day-of-month and day-of-week combined?
It follows standard Vixie cron behaviour: when both the day-of-month and day-of-week fields are restricted, a run matches if either one matches. If one is *, only the other constrains the day.
What time zone are the run times in?
The next-run preview uses your browser's local time zone, shown above the list. Real cron servers usually run in their own configured zone, so double-check where the job will actually run.
Is my data sent anywhere?
No. Parsing, validation and the run-time preview all happen locally in your browser, so nothing you type is uploaded, and the tool works offline.
Tips
- Use */n for even intervals, for example */15 in the minute field means every quarter hour.
- Remember Sunday can be written as 0 in the day-of-week field.
- Setting both a day-of-month and a weekday makes the job run whenever either matches, which is often more frequent than expected.