What is the best 20 or 30 peroxide when covering grey hair?

When covering grey hair, a 20-volume peroxide is generally recommended for achieving a natural look, as it provides enough lift while minimizing damage. It allows for effective color deposit without overly lightening the hair. A 30-volume peroxide may be used for more resistant grey hair or when lifting darker shades, but it can result in more damage. Always consider a patch test and consult a professional to determine the best option for your hair type and desired results.