The Cron Job/Crontab
To have your task run at this frequency, use the following cron:
40 */12 * * *
This cron command translates to the following (in Human-Readable format):
“Every 12 hours at 40 minutes past the hour.”
What is a Cron Job & Crontab?
A cron job is a time-based task that is set to run at specific intervals. These jobs are usually used for maintenance or automation purposes. For example, a cron job could be set to delete temporary files every week so that they don’t take up space on the server.
A crontab is a text file containing a list of commands that are executed at specified times. The commands in the crontab are executed by the cron daemon, which runs in the background and checks for new entries every minute.
Every cron job uses five fields. Here is an explanation of what each field does in this cron, which runs “every 12 hours at 40 minutes past the hour“:
FUN FACT: When configuring a cron job, you can specify the minute, hour, day of the month, month and day of the week when it should run – this gives you a lot of flexibility in terms of when your task will be performed automatically!.
You might want to set up a crontab or cron job to run every 12 hours at 40 minutes past the hour for several reasons, including:
- To run a daily backup of a database at 12:40 AM and 12:40 PM
- To send out a daily email report at 12:40 AM and 12:40 PM
- To refresh data from an external API at 12:40 AM and 12:40 PM
Similar Cron Jobs
You might also want to run a crontab:
- every 3 hours
- every 2 hours
- every 4 hours
- every 5 hours
- every 9 hours
- every hour between 2:00 am and 9:00 pm
- every hour between 6:00 am and 1:00 pm
FUN FACT: One common use for cron jobs is to send out email reminders or notifications based on certain events (such as an upcoming deadline)..
In this article, you learned how to set up a cron job that runs every 12 hours at 40 minutes past the hour. Please share this page with friends and colleagues if you find it useful.
If you have any questions, please don’t hesitate to comment below.
If you are looking for cron jobs that run at certain minutes, hours, days, weekdays, or months, or if you are looking for miscellaneous cron jobs, then check out our relevant sections, or visit our cron job cheat sheet for a list of hundreds of popular cron jobs.