Cron Expression for Every 12 Hours

0 */12 * * *

At 0 minutes past the hour, every 12 hours. Twice-daily database dumps or dependency vulnerability scans.

Field-by-field breakdown

Field	Value	Allowed range	Meaning
Minute	0	0–59	at minute 0
Hour	*/12	0–23	every 12 hours
Day of month	*	1–31	every day of the month
Month	*	1–12	every month
Day of week	*	0–6 (Sunday = 0)	every day of the week

Next 5 runs (your time zone)

Calculating upcoming runs…

Cron uses the time zone of the machine or scheduler that runs it, which is often UTC on servers.

How to use this schedule

crontab

0 */12 * * * /path/to/script.sh >> /var/log/job.log 2>&1

Kubernetes CronJob

apiVersion: batch/v1
kind: CronJob
metadata:
  name: my-job
spec:
  schedule: "0 */12 * * *"
  jobTemplate:
    spec:
      template:
        spec:
          containers:
            - name: my-job
              image: busybox
              command: ["sh", "-c", "echo running"]
          restartPolicy: OnFailure

GitHub Actions

on:
  schedule:
    - cron: '0 */12 * * *'  # UTC

Frequently Asked Questions

What is the cron expression for every 12 hours?

Use "0 */12 * * *". In plain English: At 0 minutes past the hour, every 12 hours.

What does "0 /12 * *" mean?

Minute: at minute 0; Hour: every 12 hours; Day of month: every day of the month; Month: every month; Day of week: every day of the week.