Cron pattern
Cron Expression for Every 15 Minutes
*/15 * * * * is the cron expression that fires four times per hour. Here is exactly what each field controls and when the next runs will happen.
*/15 * * * * This schedule fires on the pattern shown above; see the field-by-field breakdown below.
Next 5 run times
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Reading */15 * * * *
A cron expression has five fields: minute, hour, day of month, month, day of week.
The schedule */15 * * * * sets only the minute field and leaves everything else open:
*/15— the “step” syntax. Starting at minute 0 it takes every 15th minute: 0, 15, 30 and 45 past the hour.- First
*— every hour of the day. - Second
*— every day of the month. - Third
*— every month of the year. - Fourth
*— every day of the week.
The result is 96 runs per day, on the quarter-hour. Because the day-of-month and day-of-week fields are both stars, there is no interplay between them — every calendar day qualifies, all year round.
Why quarter-hour frequency?
Fifteen minutes is a natural middle ground between fast feedback and server load. Many MLOps and
ETL pipelines re-score a small model or sync deltas on this cadence; trading dashboards refresh quotes;
and observability stacks send a “synthetic heartbeat” every 15 minutes to prove the pipeline is alive.
Some rate-limited SaaS APIs only allow a few requests per minute, and */15 * * * * keeps
integrations comfortably under those quotas while staying fresh.
Common variations
To halve the cadence you can write */5 * * * * for every 5 minutes.
To run only at the top of each hour instead of four times an hour, switch the minute field to
0 * * * * — see the every-hour page.
You can also restrict the window with hour and weekday ranges, like
*/15 9-17 * * 1-5 for weekdays during business hours.
Note that */15 always anchors to the top of the hour (minute 0). If you need runs at
minutes 5, 20, 35, 50 instead, write 5/15 * * * * — that syntax says “start at minute 5,
step by 15.” Both are explained in the complete cron guide.
Understanding the syntax of */15 * * * *
In plain English, this schedule every 15 minutes. Here is each of the five fields and what it controls:
| Field | Value | Meaning |
|---|---|---|
| Minute | */15 | every 15 minutes |
| Hour | * | every hour |
| Day of month | * | every day of the month |
| Month | * | every month |
| Day of week | * | every day of the week |
The expression has five space-separated fields: minute hour day-of-month month day-of-week. Any field set to * means “every”.
Explore more cron patterns
Fine-tune your schedule with a related pattern, or start from scratch in the builder.