Cron: every 6 hours
Four runs a day, six hours apart, starting at midnight. The list 0 0,6,12,18 * * * says the same thing and makes the hours explicit.
Open in Cron Parser The expression is filled in: change it and watch the next runs.
Expression
0 */6 * * * Meaning
At minute 0 past every 6th hour: 00:00, 06:00, 12:00, 18:00
Next 5 runs
Your time zone
The same schedule on other platforms
| Platform | Written as | Note |
|---|---|---|
| Linux crontab | 0 */6 * * * | Five fields, in the server's local time zone. A % in the command has to be escaped as \%. |
| GitHub Actions | - cron: '0 */6 * * *' | Five fields, in UTC unless a timezone (an IANA name such as Europe/Warsaw) is set next to cron. Default branch only. The shortest interval is 5 minutes; when GitHub is busy, runs start late and some are dropped. |
| Kubernetes CronJob | schedule: "0 */6 * * *" | Five fields, in the controller's time zone unless spec.timeZone is set (Kubernetes 1.27 and later). concurrencyPolicy decides what happens when runs overlap. |
| systemd timer | OnCalendar=0/6:00 | Its own calendar syntax, in a .timer unit, local time. hourly, daily and monthly match cron, but weekly means Monday. Persistent=true catches up on runs missed while the machine was off. |
| AWS EventBridge | cron(0 0/6 * * ? *) | Six fields, the last one the year; one day field must be ?, and day of week 1 is Sunday. Rules run in UTC; EventBridge Scheduler accepts a time zone. |
| Quartz / Spring | 0 0 0/6 * * ? | Six fields, seconds first. Quartz needs ? in one of the day fields and counts Sunday as 1; Spring accepts ? and numbers days like cron. |
Common mistakes
Which midnight?
The hours are in the server's time zone, and in UTC in EventBridge rules and on GitHub Actions unless the workflow sets a
timezone. 00:00 UTC is 01:00 or 02:00 in Central Europe, and the evening before in the Americas.Other hours
Move the start of the range:
0 3-23/6 * * *runs at 03:00, 09:00, 15:00 and 21:00.0 6 * * *is once a dayWithout the slash, 6 is a single hour: 06:00, every day.