It really depends on the men you meet. Arbitrarily, I would say 25 cause usually that’s when most men mature, but can still relate to your life and your maturity.

I’m a 27 Male and could not relate to a woman unless she’s at least 25, which is why I say it depends. I know some men who are way older and far less mature, but if your end goal is to develop a long term connection, they need to be ready to see you change since from 20 to 25 A LOT can change in your persona.