Curated cron expression
Twice Hourly at :15 and :45: 15,45 * * * *
15,45 * * * * — offset from top of hour — reduces platform contention.
Meaning at a glance
15,45 * * * *
Run at 15 and 45 minutes past each hour
Twice per hour at :15 and :45.
Next-run example: At 10:07, next runs are 10:15, 10:45, 11:15.
How 15,45 * * * * works
List syntax selects specific minutes within each hour.
Avoids :00 load spikes on shared schedulers.
Preview next runs and platform conversions in CronWizard before deploying to production.
| Field | Value | Meaning |
|---|---|---|
| Minute | 15,45 | Configured as 15,45 |
| Hour | * | Every value |
| Day of month | * | Every value |
| Month | * | Every value |
| Day of week | * | Every value |
Good use cases
- Staggered sync
- Load spreading
- Partner API polling
Timezone and daylight-saving behavior
Minute marks are timezone-neutral.
Use UTC correlation IDs in logs.
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 | 15,45 * * * * | Use directly in a normal five-field user crontab. |
| Kubernetes CronJob | Ready | 15,45 * * * * | Use as spec.schedule; set spec.timeZone when local wall-clock behavior matters. |
| GitHub Actions | Ready | 15,45 * * * * | Use under on.schedule; UTC is the default and an IANA timezone may be specified. |
| Vercel Cron Jobs | Plan / behavior limit | 15,45 * * * * | The expression is valid, but Vercel always uses UTC and Hobby schedules run at most once per day. |
| AWS EventBridge Scheduler | Convert | cron(15,45 * ? * ? *) | Convert to AWS minute-first cron(...), add the required year, and use ? in one day field. |
| Spring @Scheduled | Convert | 0 15,45 * * * * | Use Spring’s six fields by prepending seconds and set zone explicitly when needed. |
| systemd timer | Convert | 15,45 * * * * | Use OnCalendar syntax and validate it with systemd-analyze calendar on the target host. |
Edge cases to check before deployment
- List is not a step — exact minutes only.
Frequently asked questions
What does the cron expression 15,45 * * * * mean?
15,45 * * * * means “run at 15 and 45 minutes past each hour.” Twice per hour at :15 and :45.
What are the next run times for 15,45 * * * *?
At 10:07, next runs are 10:15, 10:45, 11:15. Exact timestamps depend on the scheduler timezone and the current time.
What timezone does 15,45 * * * * use?
Minute marks are timezone-neutral.
Can I use 15,45 * * * * 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.