Cron expression for every 15 minutes

*/15 * * * *

Four runs an hour, at :00, :15, :30 and :45, on the quarter hour.

Runs when: every 15 minutes; every hour; every day of month; every month; any day of week.

Change it in the cron expression generator

How the five fields read

Field	Value	Reads as
Minute	`*/15`	every 15 minutes
Hour	`*`	every value
Day of month	`*`	every value
Month	`*`	every value
Day of week	`*`	every value

The next five runs

What people use it for

Usage and billing roll-ups
Pulling exchange rates or other slow-moving reference data
Backing up transaction logs on a small database

cron and rate() are not the same schedule

On AWS EventBridge you can write this as cron(0/15 * * * ? *) or as rate(15 minutes). The cron form is tied to the clock and fires at :00, :15, :30 and :45. The rate form counts from the moment the rule was created, so it can fire at :07, :22, :37 and :52. Pick the one that matches what you need.

Variations of every 15 minutes

Expression	What it does
`7-59/15 * * * *`	Every 15 minutes, offset to :07, :22, :37 and :52.
`/15 9-17 * 1-5`	Every 15 minutes during business hours on weekdays.
`/15 * * 0,6`	Every 15 minutes, weekends only.

The same schedule in four tools

Linux crontab

*/15 * * * * /path/to/command

Add it with crontab -e. It runs in the machine's time zone.

Kubernetes CronJob

spec:
  schedule: "*/15 * * * *"
  timeZone: "Etc/UTC"
  concurrencyPolicy: Forbid

timeZone is stable from Kubernetes 1.27. Without it, the controller's time zone applies. Forbid stops a new run starting while the last one is still going.

GitHub Actions

on:
  schedule:
    - cron: '*/15 * * * *'

Schedules run in UTC from the default branch, and a run can start a few minutes late when GitHub is busy. Scheduled workflows in public repositories are disabled after 60 days without repository activity.

AWS EventBridge

cron(0/15 * * * ? *)

EventBridge uses six fields, with a question mark in one of the two day fields, and rules run in UTC. Weekday numbers start at Sunday = 1, so names such as MON are safer than numbers.

Questions about every 15 minutes

What happens if a run takes longer than 15 minutes?: The next run starts at the next quarter hour while the first is still going, so two copies overlap. Guard the command with flock, or set concurrencyPolicy: Forbid on a Kubernetes CronJob.
Is */15 the same as 0,15,30,45?: Yes. Both fire at :00, :15, :30 and :45.

Nearby schedules

Cron expression for every 10 minutes: Six runs an hour.
Cron expression for every 30 minutes: Twice an hour, on the hour and half hour.
All schedules and the generator

Scheduling jobs, pipelines and cloud infrastructure is part of my DevOps engineering work.