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Cron Helper

Turn cryptic cron expressions into plain English. See what your schedule actually means and preview the next run times. Supports standard 5-field cron with lists, ranges and steps.

Cron expression

Explanation

Enter a cron expression above, or pick a preset.

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Reading a cron expression

A cron expression has five fields: minute, hour, day of month, month, and day of week. A star means "every", slashes set steps like */15 for every 15 minutes, and commas and dashes build lists and ranges. The classic gotcha: when both day-of-month and day-of-week are restricted, the job runs when either matches, not both.

Next-run preview

After decoding your expression into plain English, the tool scans forward minute by minute to find the next five actual run times in your local timezone. If nothing shows up within a year, your schedule probably contains an impossible date such as February 30.

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Cron Helper FAQs

What does */15 * * * * mean?
Every 15 minutes. The */15 in the minute field means minutes 0, 15, 30 and 45 of every hour, every day.
What is the difference between * and 0 in a field?
* means every possible value, while 0 means only zero. In the hour field, * is every hour and 0 is midnight only.
Can I use 7 for Sunday in the weekday field?
Yes, both 0 and 7 mean Sunday in standard cron, and this tool accepts either.
Why do my day-of-month and day-of-week both seem to trigger?
That is standard cron behavior: when both fields are restricted, the schedule runs when either one matches. Restrict only one of them if you want a single condition.
Are the next run times in my timezone?
Yes. The preview uses your browser's local timezone, so the times shown are the times the job would run for you.
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