Cron Builder / Explainer

Build and explain standard five-field cron schedules, validate them, and preview upcoming runs in your chosen timezone.

Opening your tool…

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How it works

1

Choose a preset or edit the five fields

2

Select an IANA timezone and click Explain schedule.

3

Read the explanation and next run times, then copy the expression.

Supported syntax is five-field Unix cron: minute, hour, day of month, month, and day of week. Numeric values, *, commas, ranges, and steps are supported, plus JAN–DEC and SUN–SAT aliases. Seconds, Quartz ?, L, W, #, random H, and @ shortcuts are not supported. If both day-of-month and day-of-week are restricted, a match in either is sufficient. Preview times use the selected timezone and account for daylight saving; your scheduler may handle skipped or repeated local times differently.

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Good to know

Which timezone is stored in the expression?

None. A five-field cron expression has no timezone field. Configure the same timezone in your actual scheduler.

Why are daylight-saving runs different?

Local times can be skipped or repeated during clock changes. This preview uses cron-parser's timezone behavior; check your scheduler's policy before scheduling critical jobs.