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Both demi-permanent and semi-permanent hair color dye can be applied at a salon or at home. The are two main differences between demi and semi-permanent hair color: the duration the color lasts and how deeply the dye penetrates the hair shaft.

Chemical Composition

Semi-permanent hair color does not contain any peroxide while demi-permanent hair color may contain low levels of ammonia or peroxide.


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Demi-permanent hair color lasts up to 20 shampoos while semi-permanent hair color only lasts up to 12 shampoos.


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Semi-permanent hair color deposits dye only on the outermost layer of hair. Demi-permanent hair color deposits dye between the cuticle and cortex of the hair shaft, making it last longer.

Gray Coverage

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Semi-permanent is a good solution for hair that has 20 percent or less gray in it. People with a higher percentage of gray hair will see better results with a demi-permanent hair color.


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Both semi-permanent hair dye and demi-permanent hair dye enhance natural color tones. Unlike semi-permanent hair dye, demi-permanent hair dye has the ability to lighten hair color.