Run a Cron Job Every 15 Minutes
*/15 fires on the quarter hours — :00, :15, :30, :45 — four times an hour. It's the classic schedule for report refreshes, cache warming, and cleanup tasks that should be regular but not aggressive.
*/15 * * * *In plain English: Every 15 minutes.
Field by field
| Field | Value | Meaning |
|---|---|---|
| Minute | */15 | every 15 minutes |
| Hour | * | every hour |
| Day of month | * | every day |
| Month | * | every month |
| Day of week | * | every weekday |
Variations
0,30 * * * *every 30 minutes — half the frequency*/15 9-17 * * 1-5every 15 minutes, weekdays, business hours7-52/15 * * * *every 15 minutes offset to :07, :22, :37, :52Tweak any of these in the crontab explainer to see the schedule in plain English and its next run times.
Frequently asked questions
What's the difference between */15 and 0,15,30,45?
Nothing at runtime — they expand to the same four minutes. Use whichever reads better in your crontab; the step form adapts if you later change the interval.
Does */15 run at the top of the hour too?
Yes — a step starts from the first value of its range, so */15 includes minute 0. If you don't want the top of the hour, use 15,30,45.
New to cron syntax? Read Cron Expressions Explained, Field by Field. Job not firing? Work through Cron Job Not Running? 10 Things to Check.