Well it would be useful if they told you where, what site?
Thankfully I use Chrome for passwords, and Chrome does list out every password that supposedly has been compromised in at least ONE way on the dark web.
But where's the integrated, automated, easy solution? There is none, other than painstakingly going to every single individual website where you use all those passwords, one by one, to change it. Something I have not done yet because in my humble opinion, I think MOST of the ultra high security on these sites is a little silly and unnecessary. I often shake my head when my car insurance account requires 2-factor authentication, or my insurance claims benefits site has some fancy system of codes it needs to sends me. Who's hacking into people car insurance online accounts, or insurance benefit claims, REALLY?? I understand banking, email, really anything that can be profitable. But some of this stuff is just ridiculous. I've never heard of a cottage industry of people who hack into your Allstate account to surreptitiously change your deductibles for sh**ts and giggles.