Question: when dying hair how much developer?
Answer: The mixing ratio is 1:2. 1 part color with 2 parts developer (1 oz. of hair color combined with 2 oz. of developer, for a total forumula mixture of 3 oz.). Pour 2 oz. of developer into a tint bowl or an applicator bottle. Add 1 oz. color. Gently shake/mix and apply color.