What age do u let baby crawl around at home and not kept in play pen all the time?

Hey Mama, Babies typically start crawling around 6-9 months. When my son started to get the hang of crawling, he got upset when he’s confined within a play pen. So since then he had free reign of the house. I had to baby proof the house, covering corners and power sockets and no dangerous or fragile items within reach. Hope that helped!