[SOLVED] “First Wednesday of the month at 9 AM” in cron?

Issue

I'm trying to schedule a task to run on the “first Wednesday of the month at 9 AM” by using a cron expression.

The best I've got so far is 0 9 * * 3 which translates to “at 09:00 on Wednesday.” But that's every Wednesday, unfortunately.

Is it even possible to express that occurence in a cron expression?

Solution

You can use this syntax

0 9 1W * *

1W will specify the first Wednesday of the month.

The answer below does not appear to work (at least according to some online tools)

---

You can take advantage of the ability to specify multiple days in the 3rd parameter, like this:

0 9 1-7 * 3

Trying the expression in https://crontab.cronhub.io/, this is how the above gets described:

At 09:00 AM, between day 1 and 7 of the month, and on Wednesday

You can be sure that one and only one of the first 7 days of the month will be Wednesday, and is also the first Wednesday of the month.

Answered By - KernelDeimos

Answer Checked By - Marie Seifert (WPSolving Admin)