About the Cron Expression Parser
Cron is the Unix scheduler that runs jobs at fixed times, and a string like 30 9 * * 1 is a cron expression. The same five-field syntax is used by crontab, GitHub Actions, Kubernetes CronJobs, AWS EventBridge, Google Cloud Scheduler, Spring @Scheduled and many CI tools.
As you type, this cron parser explains the schedule in plain English, lists the next run times and, if something is wrong, tells you which field is invalid and why. Everything runs in your browser.
How to use
- Type or paste a cron expression into the box, or pick one from Common schedules.
- Read the plain-English description and the next run time in the result box.
- Use the Builder to pick minute, hour, day, month and weekday — the expression updates automatically.
- Check the list of the next 10 run times, shown in your browser’s time zone.
Cron expression format
| # | Field | Allowed values |
|---|---|---|
| 1 | Minute | 0–59 |
| 2 | Hour | 0–23 |
| 3 | Day of month | 1–31 |
| 4 | Month | 1–12 or JAN–DEC |
| 5 | Day of week | 0–7 (0 and 7 are Sunday) or SUN–SAT |
With 6 fields, the first one is read as seconds (0–59), as in Spring and Quartz. Macros such as @daily, @weekly and @hourly are supported too.
Special characters
| Symbol | Meaning | Example | Result |
|---|---|---|---|
| * | any value | * * * * * | every minute |
| , | list of values | 0 9,18 * * * | 9:00 AM and 6:00 PM |
| - | range | 0 9 * * 1-5 | weekdays at 9:00 AM |
| / | step | */10 * * * * | every 10 minutes |
If you restrict both day of month and day of week (e.g. 0 0 13 * 5), standard cron runs when either matches — on the 13th of every month and on every Friday, not only on Friday the 13th.
FAQ
Why does my cron job run at the wrong hour?
Cron uses the time zone of the machine it runs on. Many servers, GitHub Actions and AWS EventBridge run in UTC, so convert your local time to UTC (or set the TZ / CRON_TZ variable if your system supports it).
Are L, W and # supported?
No. Last day of month (L), nearest weekday (W) and nth weekday (#) are Quartz extensions that standard crontab doesn’t understand, so this tool reports them as errors.
Which time zone are the next run times in?
They are calculated in your browser’s time zone (shown next to the list), including daylight saving time changes.
What happens with a date that doesn’t exist, like February 30?
The expression is valid syntax but never fires. The tool tells you there is no run time in the next 8 years.