View most frequent post times?

Is there any analytics website that lets you view the most frequent times that an account (competitors) use to post?
I don't just want to see the "best time to post" and I can't login with the account since I want to snoop in on what competitors do!

thanks in advance, much love!

I use the phone app for Google analytics. It shows you when users are most active. Try connecting your website to it.