Xerobit

Cron Every Minute: * * * * *

The cron expression for every minute is * * * * *. It runs 1,440 times per day, and the table below explains every field.

  • Cron expression
    * * * * *
  • Schedule
    every minute
  • Runs per day
    1,440
  • Runs per 30 days
    43,200
  • systemd OnCalendar
    *-*-* *:*:00
  • AWS EventBridge
    cron(* * * * ? *)

What * * * * * means

FieldValueMeaning
Minute*every minute
Hour*every hour
Day of month*every day
Month*every month
Day of week*every day of the week

The five fields of a standard cron expression are, in order: minute, hour, day of month, month and day of week.

When every minute runs

The first run times in a day are: 00:00, 00:01, 00:02, 00:03, 00:04, 00:05, 00:06, 00:07, 00:08, 00:09, 00:10, 00:11, .... Over time that is 1,440 per day, 10,080 per week, about 43,200 per 30 days and 525,600 per year.

Copy-ready syntax for every minute

crontab

* * * * * /path/to/script.sh >> /var/log/job.log 2>&1

GitHub Actions

on:
  schedule:
    - cron: '* * * * *'

GitHub Actions cannot run a schedule more often than every 5 minutes, so * * * * * will not work there as written. Use a 5 minute schedule or trigger the job another way.

Kubernetes CronJob

apiVersion: batch/v1
kind: CronJob
spec:
  schedule: "* * * * *"
  concurrencyPolicy: Forbid

Setting concurrencyPolicy: Forbid stops a new run from starting while the previous one is still going.

systemd timer

[Timer]
OnCalendar=*-*-* *:*:00
Persistent=true

AWS EventBridge

cron(* * * * ? *)

EventBridge cron has six fields and needs a ? in either the day-of-month or the day-of-week field. The simpler rate(1 minute) form works for fixed intervals.

When to use every minute

Health check scripts often run every minute to verify that web servers or databases remain responsive. Monitoring agents also use this cadence to push system metrics like CPU usage to a central dashboard for immediate alerting.

What can go wrong

The most common problem is overlapping runs when a job takes longer than sixty seconds to finish. Multiple instances pile up and consume memory until the server becomes unresponsive or crashes entirely.

Cron uses the time zone of the machine or service running it, so check whether that is UTC or local time before you rely on the clock times above.

Other common schedules

FAQ

What is the cron expression for every minute?

Use * * * * *. It is the standard five-field form accepted by Linux crontab, Kubernetes CronJobs and GitHub Actions.

How many times a day does * * * * * run?

1,440 times per day, or 43,200 over 30 days.

How do I test a cron expression?

Build it in the cron builder, which explains each field in plain English and lists the next run times.

More cron