Curated cron expression
Every 15 Minutes Cron Expression: */15 * * * *
Decode */15 * * * * with exact run times, field-by-field meaning, timezone and DST guidance, production use cases, and conversions for major schedulers.
Meaning at a glance
*/15 * * * *
Run every quarter hour
Four times per hour and 96 nominal runs per 24-hour day.
Next-run example: At 10:16, the next nominal runs are 10:30, 10:45, 11:00, and 11:15.
How */15 * * * * works
The minute step */15 divides each hour into four matching minute marks: 0, 15, 30, and 45. The remaining wildcards allow every hour and date.
Quarter-hour scheduling is frequent enough for fresh data but leaves more recovery time than an every-minute loop. Still, the job should finish well within 15 minutes or use a lock.
| Field | Value | Meaning |
|---|---|---|
| Minute | */15 | Minutes 0, 15, 30, and 45 |
| Hour | * | Every hour |
| Day of month | * | Every date |
| Month | * | Every month |
| Day of week | * | Every weekday |
Good use cases
- Incremental data imports
- Dashboard refresh
- Notification batching
- Certificate or endpoint checks
Timezone and daylight-saving behavior
The interval is unchanged by timezone selection; timezone controls the labels shown for each occurrence.
Use an absolute timestamp as a run key because local times can repeat when clocks move backward.
The expression does not contain a timezone. The scheduler supplies that context. Use the next-run preview above in the same IANA timezone as production, then confirm the target platform's own timezone rules.
Platform compatibility and converted expressions
The source expression is five-field Unix cron. Use the exact equivalent below rather than adding or removing fields by sight.
| Platform | Status | Expression | What to know |
|---|---|---|---|
| Unix crontab | Ready | */15 * * * * | Use directly in a normal five-field user crontab. |
| Kubernetes CronJob | Ready | */15 * * * * | Use as spec.schedule; set spec.timeZone when local wall-clock behavior matters. |
| GitHub Actions | Ready | */15 * * * * | Use under on.schedule; UTC is the default and an IANA timezone may be specified. |
| Vercel Cron Jobs | Plan / behavior limit | */15 * * * * | Valid on eligible plans; Vercel always evaluates it in UTC. |
| AWS EventBridge Scheduler | Convert | cron(0/15 * * * ? *) | Convert to AWS minute-first cron(...), add the required year, and use ? in one day field. |
| Spring @Scheduled | Convert | 0 */15 * * * * | Use Spring’s six fields by prepending seconds and set zone explicitly when needed. |
| systemd timer | Convert | *-*-* *:00/15:00 | Use OnCalendar syntax and validate it with systemd-analyze calendar on the target host. |
Edge cases to check before deployment
- */15 means quarter-hour marks, not 15 minutes after the previous run completes.
- A retry close to the next boundary can overlap the next scheduled attempt.
- At scale, choose a non-uniform offset or add jitter to avoid synchronized load.
Frequently asked questions
What does the cron expression */15 * * * * mean?
*/15 * * * * means “run every quarter hour.” Four times per hour and 96 nominal runs per 24-hour day.
What are the next run times for */15 * * * *?
At 10:16, the next nominal runs are 10:30, 10:45, 11:00, and 11:15. Exact timestamps depend on the scheduler timezone and the current time.
What timezone does */15 * * * * use?
The interval is unchanged by timezone selection; timezone controls the labels shown for each occurrence.
Can I use */15 * * * * on every scheduling platform?
No. It is a five-field Unix expression. Some platforms accept it directly, while AWS EventBridge Scheduler, Spring, and systemd require the converted form shown in the compatibility table.