Frequently asked questions
What are the five fields of a cron expression?
In order: minute (0–59), hour (0–23), day of the month (1–31), month (1–12 or JAN–DEC) and day of the week (0–7 or SUN–SAT, where both 0 and 7 mean Sunday). For example, 30 9 * * 1-5 means 09:30 on weekdays.
What do *, commas, dashes and slashes mean?
* means every value. A comma lists values (1,15), a dash gives a range (9-17) and a slash gives steps (*/15 means every 15 minutes; 0-30/10 means 0, 10, 20 and 30).
What happens when both day of month and day of week are set?
In standard cron, if both fields are restricted, the job runs when either one matches. 0 0 1 * MON runs at midnight on the 1st of every month and on every Monday. This explainer follows that rule.
Which time zone does cron use?
Cron uses the time zone of the server or service running it, which is often UTC on cloud platforms. The next run times here are shown in your own time zone, so check what your server uses.
Are seconds or years supported?
This explainer covers the standard 5-field format used by Linux crontab, Kubernetes CronJobs, GitHub Actions and most schedulers. Quartz and some other tools add a seconds field or a year field, which aren't supported here.
