Works! my hair was blonde, I colored it red and hated it so I put a dark brown on top of that and hated that too. I bought colorzap and in minutes it stripped all hair color out of my hair. It does make your hair feel bad after because It's not good for it. So I recommend a good conditioning treatment also. You will have to color your hair again after colorzap because it will leave you yellow headed like a new born baby chick. But it does what it says! Very pleased!