How much wall space do I need for a home gym mirror?

For form-checking during free weights or yoga, most reviewers recommend at least 48"x48" of total mirror surface, which is why two- and three-panel 48"x24" frameless sets are the most-reviewed configuration on Amazon. Smart mirrors are typically 50–63" tall and 20–22" wide, so they take less wall space but show only one person at a time.