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Cron Parser

cron → schedule

Explain a cron expression in words, and show when it next runs.

Cron expression

Five fields: minute, hour, day of month, month, day of week. Names like MON and JAN work, and so do the @daily-style aliases.

try

Every 15 minutes from 09:00 to 17:45, Monday to Friday.

minute
*/15
hour
9-17
day of month
*
month
*
day of week
mon-fri

next five runs, in your timezone

reading your clock…

About Cron Parser

Paste a cron expression and read back what it actually means in plain words, plus the next five times it will fire in your own timezone. Seeing real dates is what settles the question — an expression can look right and still fire on a day you did not intend.

All the usual syntax is understood: single values, ranges, lists, steps like */15, and the three-letter names for months and weekdays. The @daily, @hourly, @weekly, @monthly and @yearly aliases are expanded too, and both 0 and 7 are accepted for Sunday.

One rule is called out explicitly, because it surprises almost everyone: when both the day-of-month and day-of-week fields are restricted, cron fires when either matches, not both. So "0 0 1 * MON" runs on the first of every month AND on every Monday. When that applies, the description here says so rather than leaving you to find out in production.

Common questions

Why does my job run more often than I expected?
Almost certainly the either/or day rule. If you set both a day of the month and a weekday, cron treats them as alternatives, not as conditions that must both hold. To restrict to one, leave the other as an asterisk.
What timezone do the next runs use?
Your computer's. The expression itself carries no timezone, so the server that runs it will use whatever it is configured for — often UTC. If the times shown here look shifted from what you see in production, that difference is why.
Is @reboot supported?
It is recognised but has no schedule to show: it means "once when the machine starts", which is an event rather than a time. Nothing can predict its next occurrence.
Are there fields beyond the standard five?
Some systems add a seconds field at the front, or a year at the end, and Quartz adds L, W and # modifiers. This parser handles the standard five-field crontab syntax that Linux cron, Kubernetes CronJobs and most CI schedulers use.

This page does the work itself, in this tab. Nothing you paste is sent to a server. Close the tab and no copy remains.