Cron every 15 minutes

*/15 * * * * runs a job every fifteen minutes: on the hour and at quarter past, half past and quarter to. In the minute field, */15 picks 0, 15, 30 and 45.

When it fires

Checked at 09:58 UTC, the next five runs are:

10:00  10:15  10:30  10:45  11:00

The step counts from the start of each hour, so the runs line up with the clock rather than with the moment the job was installed. 0,15,30,45 * * * * says exactly the same thing.

Variations

*/15 9-17 * * 1-5     every quarter hour in office hours, Monday to Friday
7-59/15 * * * *       every 15 minutes, off the round minutes: :07, :22, :37, :52

The same schedule elsewhere

• GitHub Actions: cron: '*/15 * * * *'. Times are UTC, and runs can start a few minutes late when Actions is busy.
• Kubernetes CronJob: schedule: "*/15 * * * *"; set spec.timeZone if the zone matters.
• AWS EventBridge: rate(15 minutes), or cron(0/15 * * * ? *).
• systemd timer: OnCalendar=*:0/15.
• Spring @Scheduled: 0 */15 * * * *.