Hourly
0 */3 * * *Run eight times a day — 00:00, 03:00, … 21:00.
This preview is live: the table below shows the actual next run times for 0 */3 * * * in your time zone, recomputed in your browser. Change the expression, dialect, or zone to experiment, then copy the result.
0 */3 * * * means0 */3 * * * fires eight times a day at three-hour intervals starting from midnight. Because 24 divides evenly by 3, the spacing is perfectly regular all the way around the clock, ending at 21:00 and resuming at 00:00.
Three-hour cadence suits jobs that are moderately heavy and tied to a quarter-of-the-day rhythm: think batch imports, periodic full syncs, or recomputing something that changes slowly but materially over the course of a day.
Unix cron has five fields. Here is what each one is doing in this expression:
| Field | Value | Meaning |
|---|---|---|
| Minute | 0 | minute = 0 |
| Hour | */3 | every 3 (step) across hour |
| Day of month | * | every day-of-month |
| Month | * | every month |
| Day of week | * | every day-of-week |
The same cadence written for the seven cron dialects you are most likely to meet. Copy the line for the system you target — the field count and day-of-week numbering differ between them.
| Scheduler | Expression | Copy |
|---|---|---|
| Unix / crontab | 0 */3 * * * | |
| GitHub Actions | 0 */3 * * * | |
| Kubernetes CronJob | 0 */3 * * * | |
| Vercel Cron | 0 */3 * * * | |
| Quartz | 0 0 */3 * * * * | |
| Spring | 0 0 */3 * * * | |
| AWS EventBridge | 0 */3 * * * * |
0 */3 * * *Step values in the hour field only divide cleanly for factors of 24 (2, 3, 4, 6, 8, 12). */5 in the hour field fires at 0, 5, 10, 15, 20 then jumps to 0 — a 4-hour gap, not 5.
0 */3 * * * means: Run eight times a day — 00:00, 03:00, … 21:00. 0 */3 * * * fires eight times a day at three-hour intervals starting from midnight. Because 24 divides evenly by 3, the spacing is perfectly regular all the way around the clock, ending at 21:00 and resuming at 00:00.
Use 0 */3 * * * in the schedule's cron field. Step values in the hour field only divide cleanly for factors of 24 (2, 3, 4, 6, 8, 12). */5 in the hour field fires at 0, 5, 10, 15, 20 then jumps to 0 — a 4-hour gap, not 5.
EventBridge uses six fields with a required year and a ? placeholder in one day field: 0 */3 * * * *. Wrap it as cron(0 */3 * * * *) in the console or CloudFormation.
Quartz is seconds-first with a trailing year, so the equivalent is 0 0 */3 * * * *. Remember Quartz numbers Sunday as 1, the opposite of Unix.
Browse the full set of cron pattern pages, or jump to the interactive tools: the cron expression builder for designing a schedule from scratch, the cron cheat sheet for a side-by-side reference, the cron timezone translator for moving a schedule between zones and dialects, and the GitHub Actions cron picker for DST-stable CI schedules.