Your results will appear here.
Enter your values and press Calculate.
Multiply dye ounces by the developer ratio for developer ounces, then add dye and developer for the total mix. Four ounces of dye at a 1 to 2 ratio need 8 ounces of developer, 12 ounces total. The reverse works too: for a target total, dye equals total divided by one plus the ratio.
Developer ounces equal dye ounces times the developer ratio, and total mix ounces equal dye plus developer. Four ounces of dye at a 1 to 2 ratio need 8 ounces of developer, 12 ounces total, while 40 grams of color at a 1 to 1.5 ratio needs 60 grams of developer, 100 grams total. The reverse hair dye calculator step works when you know the target total: dye equals total divided by one plus the ratio, so a 120 gram total at 1 to 2 needs 40 grams of dye and 80 grams of developer.
A 1 to 1 ratio means equal parts color and developer, and suits maximum gray coverage and deposit only color. A 1 to 1.5 ratio is the standard for many permanent colors, balancing deposit and lift at 1 to 2 levels. A 1 to 2 ratio suits high lift color and toning, with a more diluted, lighter result. Brand lines differ: L Oreal Majirel commonly uses 1 to 1.5, Wella Koleston and Schwarzkopf Igora Royal use 1 to 1, and Wella Color Touch demi permanent uses 1 to 2, so always follow the product instructions over any general chart.
Developer volume controls lift, while the mixing ratio controls amount and consistency, so change volume, not amount, when you want more lift. Ten volume, 3 percent peroxide, is for deposit only work like demi permanent toners and going darker. Twenty volume, 6 percent, covers gray and lifts about one level and suits most permanent color. Thirty volume, 9 percent, lifts about two levels for high lift blondes, and 40 volume, 12 percent, gives maximum lift but is harsh, so professionals mostly reserve it for off scalp lightening with bleach.
For a hair dye amount calculator estimate, a pixie cut needs about 1.5 ounces of total mixture, chin length hair about 2 ounces, shoulder length medium density hair about 3 ounces, mid back hair about 4 to 6 ounces, and waist length hair about 6 to 8 ounces. Thick or coarse hair needs 25 to 50 percent more, fine hair needs about 25 percent less, and a root touch up needs only about 1 ounce of dye before developer. Measure dye and developer in the same unit, ounces or grams, and never mix units in one bowl.
Too much developer dilutes the pigment and gives a thinner, lighter, patchier result, while too little developer leaves a thick mixture that cannot process evenly. Mixed color cannot be saved for later use, so mix for one application at a time. Weigh powder bleach on a scale rather than scooping by volume, mix in a plastic or glass bowl, never metal, wear gloves, and always patch test a new color before a full application.
Enter your dye amount and the ratio printed on your color product, using 1 for 1 to 1, 1.5 for 1 to 1.5, and 2 for 1 to 2. For mixing two hair colors, add both color amounts together first, then multiply the combined color by the ratio, because the ratio applies to the whole color portion, not to each shade separately. Follow the product timing, rinse thoroughly, and keep the finished mixture off skin and clothing.
It means you use twice as much developer as dye. For example, 1 ounce of hair dye needs 2 ounces of developer, and 2 ounces of dye need 4 ounces of developer, giving 3 ounces and 6 ounces of total mixture.
Many permanent colors use 1 part dye to 1 part developer, while 1 to 1.5 is the standard for several major lines. High lift colors and toners often use 1 to 2. Always follow your product instructions, since brand ratios differ.
No, most permanent and semi permanent hair dyes require a developer to activate the color. Without developer the color stays on the surface, rinses out quickly, and gives no gray coverage and no lift.
Too much developer dilutes the pigment, so the result is lighter, thinner, and often patchy, with weaker gray coverage. Too little developer has the opposite problem: a thick mixture that spreads unevenly and processes inconsistently.
For long hair past mid back with medium density, plan on 4 to 6 ounces of total mixture, or about 120 to 180 grams. Waist length hair can need 6 to 8 ounces, especially if it is thick or coarse, while fine hair needs about 25 percent less.
Ten volume, 3 percent peroxide, is for deposit only work and toning. Twenty volume, 6 percent, covers gray and lifts one level. Thirty volume, 9 percent, lifts two levels. Forty volume, 12 percent, gives maximum lift but is harsh, so it is mostly used for off scalp lightening.
Yes. Add the two color amounts together first, then multiply the combined color by the developer ratio. Keep the shade proportions you want, for example equal parts for a balanced blend, and mix only what you need for one application.
No. Once dye and developer are mixed, the chemical reaction starts and the mixture cannot be stored for a later session. Mix a fresh batch each time, and use any small leftover only for a strand test during the same session.