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Cron Every 15 Minutes: */15 * * * *

The cron expression for every 15 minutes is */15 * * * *. It runs 96 times per day, and the table below explains every field.

  • Cron expression
    */15 * * * *
  • Schedule
    every 15 minutes
  • Runs per day
    96
  • Runs per 30 days
    2,880
  • systemd OnCalendar
    *-*-* *:0/15:00
  • AWS EventBridge
    cron(0/15 * * * ? *)

What */15 * * * * means

FieldValueMeaning
Minute*/15every 15th minute, starting at minute 0
Hour*every hour
Day of month*every day
Month*every month
Day of week*every day of the week

The five fields of a standard cron expression are, in order: minute, hour, day of month, month and day of week.

When every 15 minutes runs

The first run times in a day are: 00:00, 00:15, 00:30, 00:45. Over time that is 96 per day, 672 per week, about 2,880 per 30 days and 35,040 per year.

Copy-ready syntax for every 15 minutes

crontab

*/15 * * * * /path/to/script.sh >> /var/log/job.log 2>&1

GitHub Actions

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

GitHub Actions runs scheduled workflows in UTC and may start them a few minutes late when GitHub is busy.

Kubernetes CronJob

apiVersion: batch/v1
kind: CronJob
spec:
  schedule: "*/15 * * * *"
  concurrencyPolicy: Forbid

Setting concurrencyPolicy: Forbid stops a new run from starting while the previous one is still going.

systemd timer

[Timer]
OnCalendar=*-*-* *:0/15:00
Persistent=true

AWS EventBridge

cron(0/15 * * * ? *)

EventBridge cron has six fields and needs a ? in either the day-of-month or the day-of-week field. The simpler rate(15 minutes) form works for fixed intervals.

When to use every 15 minutes

Many organizations schedule lightweight database backups or incremental data syncs every fifteen minutes to limit potential data loss. Monitoring dashboards also refresh metric aggregations on this cadence to keep charts current.

What can go wrong

Fifteen minute intervals can trigger rate limits on third party APIs if multiple jobs query the same endpoint simultaneously. Spreading requests across the window helps avoid hitting those external thresholds.

Cron uses the time zone of the machine or service running it, so check whether that is UTC or local time before you rely on the clock times above.

Other common schedules

FAQ

What is the cron expression for every 15 minutes?

Use */15 * * * *. It is the standard five-field form accepted by Linux crontab, Kubernetes CronJobs and GitHub Actions.

How many times a day does */15 * * * * run?

96 times per day, or 2,880 over 30 days.

How do I test a cron expression?

Build it in the cron builder, which explains each field in plain English and lists the next run times.

More cron