About cron expressions
This tool explains a cron expression in plain English and shows when it will next run. Enter a standard five-field crontab schedule and it describes the timing and lists the next run times in your local time. It runs entirely in your browser.
How Crontab Describer works
How to use it
- Enter a 5-field cron expression (minute, hour, day-of-month, month, day-of-week).
- Read the plain-English description.
- Check the next run times.
Supported syntax
It understands * (every), ranges like 1-5, steps like */5, and lists like 1,15. The next-run times are computed by scanning forward from now.
Common uses
- Understand a cron schedule
- Check when a cron job runs next
- Debug a crontab entry
- Learn cron syntax
- Verify a schedule before deploying
- Explain a cron to a colleague
- Plan job timing
- Read an unfamiliar cron
Frequently asked questions
What format does it expect?
A standard 5-field cron expression.
What do the fields mean?
Minute, hour, day-of-month, month and day-of-week.
Does it show the next runs?
Yes — the next five, in your local time.
Does it support steps and ranges?
Yes — */5, 1-5 and 1,15 all work.
Is my expression uploaded?
No — it runs in your browser.
Does it support seconds or @reboot?
It handles the standard 5-field format, not special strings.
Is it free?
Yes — completely free with no sign-up.