Run a Cron Job Every Minute
Five asterisks is the simplest possible cron expression: every field matches everything, so the job fires once a minute, every minute of every day. It's the highest frequency standard cron supports — and often a sign you should consider whether the job really needs to run that often.
* * * * *In plain English: Every minute.
Field by field
| Field | Value | Meaning |
|---|---|---|
| Minute | * | every minute |
| Hour | * | every hour |
| Day of month | * | every day |
| Month | * | every month |
| Day of week | * | every weekday |
Variations
* * * * 1-5every minute, but only on weekdays* 9-17 * * *every minute during business hours (09:00–17:59)*/2 * * * *every 2 minutes — halves the loadTweak any of these in the crontab explainer to see the schedule in plain English and its next run times.
Frequently asked questions
Can cron run more often than every minute?
Not in standard cron — the minute is its smallest unit. Some schedulers accept a sixth seconds field (e.g. */30 in front for every 30 seconds), but that's an extension. For sub-minute work, use a long-running process or a queue instead.
Is running a job every minute safe?
Only if the job reliably finishes in under a minute. If it can run long, add a lock (flock on Linux) so overlapping runs don't pile up.
New to cron syntax? Read Cron Expressions Explained, Field by Field.