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Cronjob.de › Crontab reference › Every 15 minutes

Cron job every 15 minutes

For "every 15 minutes" you write */15 * * * *. The job runs on the hour, at quarter past, half past and quarter to, four times an hour and 96 times a day.

*/15 Minute 0-59
* Hour 0-23
* Day 1-31
* Month 1-12
* Weekday 0-7

Open and adjust in the crontab generator ›

Meaning

What the expression says exactly

*/15 means: in steps of 15, starting at minute 0. That gives minutes 0, 15, 30 and 45. The list 0,15,30,45 * * * * means the same, and some interfaces display the expression in that form.

Every quarter hour is a typical interval for syncing with other systems: stock levels, prices, feeds or calendars. How often it really needs to be depends on how often the data changes on the other side.

The next runs

  • Sat, 14 Nov 2026, 01:15
  • Sat, 14 Nov 2026, 01:30
  • Sat, 14 Nov 2026, 01:45
  • Sat, 14 Nov 2026, 02:00
  • Sat, 14 Nov 2026, 02:15

Calculated in German time when this page was loaded.

Variants

Similar schedules

*/15 7-19 * * 1-5 Every 15 minutes on weekdays from 7:00 to 19:45. Adjust
5,20,35,50 * * * * Every quarter hour, but offset by five minutes. Also possible on the free plan. Adjust
*/15 0-6 * * * Every quarter hour only at night until 6:45, for example for a large import in chunks. Adjust
*/15 8-23 * * * Every quarter hour from 8 am until 23:45. Adjust

Watch out for

Typical mistakes with this interval

15 * * * * is hourly

Without the slash, the 15 stands for minute 15. The job then runs once an hour at quarter past, not four times.

The slash in the wrong field

If */15 is in the second field, 0 */15 * * *, the step applies to hours: the job runs at 0:00 and at 15:00. That easily happens when rearranging an expression.

Syncs need a lock

If a sync takes longer than 15 minutes for once, for example because the other side answers slowly, the next run starts anyway. Have the script note that a run is in progress and stop a new one right away.

Own server

How it looks in the crontab

Open with crontab -e and add one line. The first starts a PHP script directly, the second calls an address. Replace paths and address with your own.

*/15 * * * * /usr/bin/php /pfad/zu/skript.php >/dev/null 2>&1
*/15 * * * * curl -fsS https://ihre-domain.de/cron.php >/dev/null

Without your own server

How it works at Cronjob.de

No command-line access needed: you enter the address of your script and click the schedule together. You can also type the expression above directly, or describe the interval in one sentence and have it suggested. Cronjob.de uses German time.

Five cronjobs are free forever, on the five-minute grid. One-minute intervals start with Plus. How to prepare a script on shared web space for this is explained in the web space guide.

FAQ

Common questions

Is */15 the same as 0,15,30,45?
Yes. In the minute field both give exactly the same four points in time.
Is this possible on the free plan?
Yes. All four minutes are divisible by five. The free Cronjob.de plan includes five cron jobs for good.
Does the first run happen 15 minutes after saving?
No, at the next matching quarter hour. If you save at 10:52, the first run is at 11:00.

Create your cronjob now

Create an account, enter the address, click the schedule. Five cronjobs are free forever, the first 14 days run on the Unlimited plan.

Start for free To the crontab generator

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