* Hair type: Porous hair holds color better than smooth hair.
* Initial hair color: Darker hair holds color longer than lighter hair.
* Frequency of washing: Frequent washing fades color faster.
* Water quality: Hard water can strip color more quickly.
* Product quality: Higher quality demi-permanent hair color tends to last longer.
Here's a breakdown of expected longevity:
* 4 weeks: For individuals with very porous hair, who frequently wash their hair, or use hard water.
* 6 weeks: For individuals with average hair porosity and wash frequency, and use moderate water hardness.
Note: Demi-permanent hair color fades gradually, so you'll see a gradual change in your hair color over time, unlike permanent hair color which fades abruptly.