My friend and I did my whole head with 1 and a half bottles of poison. I have wavy, long dark brown hair. My hair reaches to the top of my butt, so I got two bottles just in case. I have enough left over for touch ups and adding to my conditioner. I did not want to bleach because I wanted a dark red anyway. This was able to give me the exact color I wanted. So happy with it!! It has faded a bit but its still visibly red, especially in the sun. I let the dye sit on my head for 3ish 4ish hours.