How do I know what developer volume to use?

The developer volume depends on how many levels of lift you need. 10 vol deposits colour only (going darker or same level). 20 vol lifts 1-2 levels. 30 vol lifts 2-3 levels. 40 vol lifts 3-4 levels. Never use a stronger developer than needed — it causes unnecessary damage.

What is a neutralising tone?

Neutralising uses the opposite colour on the colour wheel to cancel unwanted tones. Blue neutralises orange. Violet neutralises yellow. Green neutralises red. This is why ash (blue/green) tones are used when lifting warm hair to prevent brassiness.

How does grey coverage affect formulation?

Grey hair has no natural pigment, so it does not absorb colour easily. For over 50% grey, mix equal parts fashion shade with a natural base shade at the same level. For over 75% grey, use more natural base. The natural base provides the missing underlying pigment.

What are hair colour levels?

Hair colour levels range from 1 (black) to 10 (lightest blonde). Each level represents a degree of lightness. When lifting hair, you reveal underlying warm pigments: red-orange at levels 4-5, orange at 6-7, and yellow at 8-9. These must be neutralised for cool results.

CutCalcs

Colour Wheel Calculator — Hair Colour Theory & Mixing

Calculate developer volume, mixing ratios and neutralising tones for hair colour formulation.

Starting Level

1 = black, 10 = lightest blonde

Target Level

Desired result level

Starting Tone

Select an option for starting tone

Target Tone

Grey Coverage

Percentage of grey/white hair

How We Calculate This

This calculator determines the correct developer volume, processing time, and mixing ratio based on starting and target levels, tone preferences, and grey coverage percentage.

Developer selection

10 vol: deposit only (same or darker)
20 vol: 1-2 levels lift
30 vol: 2-3 levels lift
40 vol: 3-4 levels lift

Frequently Asked Questions

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Processing Time by Hair Type Calculator

Adjust chemical processing times based on hair type, condition and room temperature.

Last updated: March 2026

All calculations are estimates. Always perform a strand test before chemical services.