Cron job every 12 hours
0 */12 * * * On the hour, every 12 hours
Typical use: twice-daily backups. Try it below — change any field and see the next runs in your timezone.
On the hour, every 12 hours
Valid
- 1Mon, Sep 28, 2026, 12:00 AM
- 2Mon, Sep 28, 2026, 12:00 PM
- 3Tue, Sep 29, 2026, 12:00 AM
- 4Tue, Sep 29, 2026, 12:00 PM
- 5Wed, Sep 30, 2026, 12:00 AM
- 6Wed, Sep 30, 2026, 12:00 PM
- 7Thu, Oct 1, 2026, 12:00 AM
- 8Thu, Oct 1, 2026, 12:00 PM
- 9Fri, Oct 2, 2026, 12:00 AM
- 10Fri, Oct 2, 2026, 12:00 PM
Field by field
| Field | Value | Meaning |
|---|---|---|
| Minute | 0 | minute 0 |
| Hour | */12 | every 12 hours |
| Day of month | * | every day |
| Month | * | every month |
| Day of week | * | every day |
The same schedule on every platform
The five fields mean the same thing everywhere, but each scheduler wraps them differently — and AWS and Quartz number weekdays from 1 (Sunday), not 0.
0 */12 * * * /path/to/script.sh >> /var/log/job.log 2>&1spec:
schedule: "0 */12 * * *"GitHub ActionsRuns in UTC.
on:
schedule:
- cron: '0 */12 * * *'AWS EventBridgeEventBridge weekdays are 1–7 (1 = Sunday) and one day field must be ?.
cron(0 0/12 * * ? *)
# or, simpler:
rate(12 hours)Quartz (Java)Seconds first; weekdays 1–7 with 1 = Sunday.
0 0 */12 * * ?Spring @ScheduledSpring adds a seconds field but keeps Unix weekday numbers.
@Scheduled(cron = "0 0 */12 * * *")[TimerTrigger("0 0 */12 * * *")]Running a job every 12 hours
What is the cron expression for every 12 hours?
0 */12 * * *. In plain English: on the hour, every 12 hours. It works in standard 5-field cron — Linux crontab, Kubernetes and GitHub Actions.How do I schedule a job every 12 hours in AWS EventBridge?
Use
cron(0 0/12 * * ? *) or the simpler rate(12 hours). EventBridge needs six fields (a year at the end), a ? in one of the day fields, and numbers weekdays 1–7 starting on Sunday.What timezone does "0 */12 * * *" run in?
Cron uses the server's timezone. Kubernetes CronJobs default to the controller's timezone (set
spec.timeZone on 1.27+), GitHub Actions and AWS EventBridge rules always use UTC. Use the timezone picker above to see the next runs in your own time.