What does */5 * * * * mean?

In a 5-field expression it means minute 0, 5, 10, and so on, every hour, every day. The schedule fires every 5 minutes.

What is the order of the 5 fields?

Minute, hour, day of month, month, day of week. Ranges are 0-59, 0-23, 1-31, 1-12, and 0-7 where both 0 and 7 are Sunday.

What is the difference between standard cron and Quartz?

Quartz adds a seconds field and uses ? when day-of-month or day-of-week should be left unset. It also supports L, W, and #. Standard 5-field cron does not.

What timezone do GitHub Actions and Vercel Cron use?

UTC. A schedule of 0 9 * * 1-5 runs at 09:00 UTC, which is not 9am in every local timezone.

How do I run every weekday at 9am?

Use 0 9 * * 1-5. That is minute 0, hour 9, Monday through Friday. Set the timezone here to the zone you mean, and remember hosted crons stay on UTC.

How do day-of-month and day-of-week combine?

In standard cron, if both are restricted, the job runs when either matches. That is OR, not AND. Quartz avoids the ambiguity by setting one of them to ?.

Cron expression builder

Build or paste a cron schedule, read it in plain English, and see the next run times.

In A cron expression, a dialect, a timezone, and field chips for minute, hour, day, month, and weekday./Out Plain English, the next 10 runs, a field breakdown, and snippets for crontab, GitHub Actions, Vercel, Kubernetes, and node-cron.

How to use it

1Pick a preset or build fieldsStart from a preset or set minute, hour, day, month, and weekday. The expression stays in sync with the fields.
2Read the English and check the next runsThe sentence and the next 10 times use the timezone you pick. Compare them with UTC before you deploy.
3Copy for crontab, GitHub Actions, Vercel, or KubernetesEach snippet is ready to paste. GitHub Actions and Vercel Cron stay on UTC.