Cron Expression

Since version 1.8.0, Issue Reminders add-on support cron expression as period specification. This guide will helps you to understand how it works but you can use any other tutorial on cron expressions because it is a standard, not specific to Issue Reminders.

Cron Expression Testing

You can test your cron expressions on https://crontab.guru

Format

A cron expression consist of 5 parts.

MIN HOUR DOM MON DOW

Field	Description	Allowed Value
MIN	Minute field	0 to 59
HOUR	Hour field	0 to 23
DOM	Day of Month	1-31
MON	Month field	1-12
DOW	Day Of Week	0-6 (Sun, Mon, Tue, Wed, Thu, Fri, Sat)

Things to Know

Resolution of all reminders are 5 minutes, so you can't create a reminder with a period of less than 5 minutes. Even if you can write a cron expression it will not fire every minute, it will only fire at every 5 minutes.

Example Cron Expressions

Cron Expression	Explanation
0 0 * * *	Every hour, for example 13:00, 14:00.
30 0 * * *	Every half an hour, for example 13:30, 14:30.
0 0 * * *	Same with 1st example. Every hour.
0 0 1 1 *	Every year at 12:00 AM on 1 of January.
0 7 L * *	Last day of every month at 07:00 AM.
0 19 * * 1	Every Monday on 19:00.
30 8 1-7 * 1	First Monday of every month at 08:30 AM.
15 10 * * 1,5	Every Monday and Friday at 10:15 AM.
15 10 * * 1-5	Every weekday (Mon-Fri) at 10:15 AM.
0 0 1 1,6 *	At 00:00 on day-of-month 1 in January and June.
* * * * *	Every minute. But not valid for Issue Reminders add-on. It will only work with a period of 5 minutes as explained at Things to Know Section.
* 0 * * *	Every minute between 12:00 AM and 01:00 AM of every day. It will only work with a period of 5 minutes as explained at Things to Know Section.