Pictures of your space and mirror may help you get advice.

In the bathroom with my pivot mirror, there is 12” from the bottom edge of the mirror to the top of the vanity counter. In the bathroom with my oak trimmed longer rectangular mirror, there is 9” from the bottom edge of the mirror to the top of the vanity counter. You have to see at what level your mirror looks best above your counter. It depends on the mirror length and how you want it to look. I think you have to personalize it for each space❣️