What Developer Ratio Do I Need? Colour Mix Calculator
The short answer
Standard permanent colour is mixed 1:1 with developer, high-lift blonde is usually 1:2, and toners vary by brand between 1:1 and 1:2. Enter your colour weight and the ratio printed on the tube, and the developer weight is colour weight multiplied by the ratio.
The rule
Developer weight equals colour weight multiplied by the ratio. For 60 grams of colour at 1:1 you need 60 grams of developer; at 1:2 you need 120 grams.
Weigh, do not eyeball. Volume measures are the single most common source of an unpredictable mix, because a scoop of cream developer and a scoop of liquid developer are not the same weight.
Standard ratios by product
| Product | Typical ratio | Notes |
|---|---|---|
| Permanent colour | 1:1 | Follow the tube if it differs |
| High-lift blonde | 1:2 | Off-scalp only |
| Demi-permanent toner | 1:1 to 1:2 | Brand dependent |
| Semi-permanent direct dye | 1:0 to 1:1 | Often used neat |
Frequently asked
Can I use less developer to make the colour stronger?
No. Changing the ratio changes how the colour processes, not just its strength. A thicker mix processes unevenly and can leave the mid-lengths under-developed.
What if the tube does not state a ratio?
Default to 1:1 for permanent colour and confirm with the brand. Guessing on a corrective service is how a formula becomes a correction.
Keep reading
- Hair Color Mixing Calculator — Exact Colour and Developer AmountsExact colour and developer amounts for any brand and ratio, scaled to the hair in the chair — free, no login.
- How Many Grams of Colour Do I Need Per Service?Root touch-up, full-head, or foils — how much colour to mix so you stop wasting tubes.
- What Developer Do You Use for a Root Touch-Up?Deposit or lift, and how much — the decision tree for developer on a root retouch.
- Which Developer Volume Lifts How Many Levels?What each volume can and cannot do, and why the standard rule breaks on resistant grey and lightened hair.
Part of Tools in the S2 Academy.