Linux

Cron explained

Turn a cron line into plain language and see when it runs, or build your own.

Cron line (5 fields, or @daily, @hourly and similar)

Minute

Hour

Day of the month

Month

Day of the week

What does this mean?

A cron line consists of five fields: minute, hour, day of the month, month, and day of the week. A * means "every", */5 means "every 5", 1-5 is a range (Monday through Friday) and commas create a list (1,15). Sunday is 0 (or 7).

Note: if both "day of the month" and "day of the week" are filled in, the task runs on either one. The times above are in your browser's time zone; a server may use a different time zone (often UTC). In a user's own crontab (crontab -e) you only put the five fields followed by the command.