Cron Expression for Every 4 Hours

0 */4 * * *

0 */4 * * * runs six times a day at 00:00, 04:00, 08:00, 12:00, 16:00 and 20:00. Four divides 24 evenly, so the six-run pattern repeats identically every day.

Next runs, in your timezone

 

Reading the expression

*/4 in the hour field is the list 0,4,8,12,16,20 with the minute pinned to :00. As with every hour-step schedule, the pinned minute is load-bearing — * in the minute field turns 6 runs a day into 360.

0 */4 * * * /path/to/job.sh >> /var/log/myjob.log 2>&1

Equivalent expressions

  • 0 0,4,8,12,16,20 * * *explicit list — identical schedule
  • 0 2-22/4 * * *same cadence at 02:00, 06:00, … for quieter hours

Run a SQL query on this schedule

If the job behind this schedule is a database query, you can skip the server and the crontab: SaturnSQL runs saved SQL queries on a cron expression — this exact syntax, with a real timezone field — and delivers the results to Google Sheets or Slack. Minimum interval 5 minutes.