Run a cron job every 30 minutes
“At every 30th minute.”
Fires at :00 and :30 — 48 runs a day. Half-hourly is the classic compromise for jobs that are too heavy for minutes-level frequency but too important to wait an hour, like inventory sync or search-index refresh.
*/30 * * * *Next 5 runs
Computing from your local clock…
Field by field
| Field | Value | Meaning |
|---|---|---|
| Minute | */30 | every 30 starting from 0 |
| Hour | * | every value |
| Day of month | * | every value |
| Month | * | every value |
| Day of week | * | every value |
Typical uses
- Re-indexing changed records into a search engine
- Syncing inventory or pricing between systems
- Generating pre-computed recommendations
Worth knowing: Equivalent to the list form 0,30 * * * * — some teams prefer the explicit list because it survives copy-paste into dialects with quirky step support.
Related schedules
Need a different schedule? Build and test any cron expression with live explanation and next-run preview, or read the complete cron syntax guide.