Cron Reference

Every Hour

The 0 in the minute field means the job fires exactly at the top of each hour (:00). The * s allow any hour, day, month, and weekday.

* * * * * runs every minute (60× per hour). 0 * * * * runs only at the top of the hour (1× per hour).

Runs once at the top of every hour, 24 times per day.

Cron Expression

0 * * * * Test in tool

Every hour at :00

Expression Breakdown

Minute	Hour	Day	Month	Weekday
0	*	*	*	*
0	any	any	any	any

Times are relative to the server's local clock at page load.

Run crontab -e and add this line:

0 * * * * /path/to/your/script.sh

scheduler.add_job(my_func, 'cron',
    minute='0',
    hour='*',
    day='*',
    month='*',
    day_of_week='*')

on:
  schedule:
    - cron: '0 * * * *'

What does 0 * * * * mean?

The 0 in the minute field means the job fires exactly at the top of each hour (:00). The *s allow any hour, day, month, and weekday.

How is 0 * * * * different from * * * * *?

* * * * * runs every minute (60× per hour). 0 * * * * runs only at the top of the hour (1× per hour).