Cron expression for every 30 minutes
Runs the job twice an hour, on the hour and on the half hour.
*/30 * * * *
Every 30 minutes
Field by field
- Minute · 0–59
*/30every 30th minute - Hour · 0–23
*every hour - Day of month · 1–31
*every day of the month - Month · 1–12 or JAN–DEC
*every month - Day of week · 0–7 or SUN–SAT
*every day of the week
Next runs in your local time
Where this cron expression shows up
- Half-hourly syncs with a CRM or a billing system
- Refreshing a dashboard cache before people look at it
- Batching notification emails so nobody gets twenty at once
Common variations
-
The same, written as a list
0,30 * * * * At 0 and 30 minutes past the hour
-
Every fifteen minutes
*/15 * * * * Every 15 minutes
-
Every hour, on the hour
0 * * * * Every hour
Ranges, steps, and names are spelled out on the cheat sheet.