How long does the colour last and what makes it fade faster or slower?

The colour deposits on the outer hair layer and washes out gradually — typically over 3–8 shampoos, but this varies widely. Porous, pre-lightened, or grey hair grabs pigment more strongly, so the tone may look more intense initially and linger longer. On less porous, natural medium-brown to light-blonde hair the deposit is sheerer and fades quicker. Hot water, clarifying shampoos, frequent washing, and UV exposure accelerate fading; cooler water, sulfate-free shampoos, and less frequent washing help extend it. Because the product does not use oxidative chemistry, there is no permanent change to the hair structure — the colour simply lifts away as the cuticle is cleansed. If you want a longer-lasting refresh, you can repeat use every few washes; the 40 ml sachet is sized for roughly one application on shoulder-length hair.