* The shade of purple: A very light, pastel purple will be easier to cover than a deep, vibrant purple.
* The shade of brown: A dark brown is more likely to cover the purple completely than a light brown.
* The condition of your hair: Porous or damaged hair may absorb color unevenly.
* The undertones of the purple and brown dyes: Purple can have blue or red undertones, which can influence the final color. Similarly, brown dyes can have warm (red/gold) or cool (blue/ash) undertones.
Possible Outcomes:
* Muddy Brown: This is the most likely outcome. The purple will mix with the brown, creating a dull, murky brown.
* Ashy Brown: If the purple has strong blue undertones and you use an ashy brown dye, your hair might turn an ashy or greenish-brown.
* Warm Brown: If the purple has strong red undertones and you use a warm brown dye, you might end up with a warmer, reddish-brown.
* Uneven Color: You might get an uneven color, with some parts of your hair looking brown and others still showing hints of purple.
Recommendations:
1. Color Correction: Ideally, you would use a color corrector to neutralize the purple before applying the brown dye. An orange or yellow-based color corrector can help cancel out the purple.
2. Fill the Hair: If you don't use a color corrector, consider using a "filler" dye that is a warm tone, like a reddish-brown or copper, *before* applying your desired brown. This helps add back the warm tones that the purple may have stripped away.
3. Choose a Darker Brown: Opt for a slightly darker brown than your desired shade to ensure better coverage.
4. Strand Test: Always do a strand test on a small, hidden section of your hair before applying the dye to your entire head. This will give you a better idea of how the colors will react and prevent any surprises.
5. Consult a Professional: For the best and most predictable results, especially if you have a very vibrant or stubborn purple, it's always recommended to consult a professional hairstylist. They can assess your hair and use the right products and techniques to achieve your desired brown color.