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Hair Color Mixing Ratios Explained: 1:1, 1:1.5 and 1:2, Brand by Brand

By the Formula Finder teamUpdated 4 min read

You picked the perfect shade. You picked the right developer. Then you eyeballed the bowl, and the color came out darker, patchier or weaker on gray than the chart promised.

The mixing ratio is the quiet part of every formula, and it changes everything. Here is what the numbers mean, how to measure them properly, and what the major brands actually call for.

What a mixing ratio means

A mixing ratio tells you how much developer to use for every part of color. The first number is always the color. The second number is the developer.

  • 1:1 means equal parts. 30 g of color plus 30 g of developer.
  • 1:1.5 means one and a half parts developer. 40 g of color plus 60 g of developer.
  • 1:2 means double the developer. 30 g of color plus 60 g of developer.

The ratio is set by the manufacturer for that exact line. It is not a style choice, and it is not interchangeable between brands.

Why the ratio matters

Permanent and demi color need the right amount of developer to fully develop. When the balance is off, the color behaves differently than the chart shows.

  • Too little developer: the mix is thick and under-developed. You can get less lift, darker or muddier results and weaker gray coverage.
  • Too much developer: the color is diluted. You can get a sheer, washed-out result, less deposit and a runny mix that is hard to control at the scalp.

If your client's result never matches the swatch, check the ratio before you blame the shade.

Measure by weight, not by eye

Most brands write their ratios by weight. A digital color scale is the most accurate tool in your station.

  1. Put the empty bowl on the scale and zero it.
  2. Add the color and note the grams.
  3. Multiply that number by the second number in the ratio. That is your developer amount.
  4. Zero the scale again and add the developer.

Example: you squeeze out 40 g of a 1:1.5 color. 40 x 1.5 = 60 g of developer.

Mixing two shades together? Add the shades up first, then work out the developer from the total. 20 g of one shade plus 20 g of another is 40 g of color, so a 1:1 line takes 40 g of developer.

Mixing ratios by brand

These come straight from each line's manufacturer chart, as listed on our free Color Charts. Always check the current chart for your country, since lines get updated.

Permanent color

Demi-permanent and gloss

Notice the pattern. Most permanent lines mix 1:1, a few run 1:1.5, and high-lift blondes almost always go to 1:2. The extra developer in a high-lift mix is what gives it the lifting power to reach those pale levels.

Common mistakes to avoid

  • Carrying one brand's ratio to another. A stylist trained on 1:1 lines can under-mix Majirel or ChromaSilk without realizing it.
  • Using the wrong developer. Most lines are built for their own developer. Swapping brands can change the result.
  • Forgetting the high-lift exception. Special Blonde, Highlifts and Ultra.Blonde shades usually need 1:2 and a higher volume.
  • Mixing too far ahead. Once color and developer meet, the reaction starts. Mix right before you apply.
  • Not writing it down. If you adjusted anything at the bowl, note it in your client's file so the next visit starts from what worked.

Quick checklist

  • Find the ratio on the line's chart, not from memory.
  • Weigh the color first, then multiply for the developer.
  • Use the developer the line was built for.
  • Double-check high-lift and toning shades. They often break the line's usual rule.
  • Record the exact grams you used.

If you are still learning which developer volume to pair with each job, start with our guide to developer volume, and our breakdown of permanent vs demi vs semi-permanent color.

Find any line's ratio in seconds

Our free Color Charts list the mix ratio, developer, processing time and gray coverage for 23 professional brands and more than 5,700 shades, no sign-up needed.

Formula Finder takes it a step further. Upload your client's inspo pic and current hair, pick your brand, and get a step-by-step formula with the shades, developer, ratios, timing and application built on that brand's real chart.

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