You can color synthetic hair extensions with a semi or demi color. Synthetic hair extensions will not color. The best way to color hair extensions is to get the lightest shade available and then color them to the desired color. Note that with hair extensions will process faster so you shouldn’t leave the hair color on as long. So many are coloring their hair extensions to get her perfect shade or to achieve a chemical free rainbow look.
Depending on the quality of hair and where it’s from, it’s safe to say that the synthetic hair extensions have already been color treated. Remy hair extensions are from India and the raw material is virgin (never colored nor chemically treated with perms or straighteners.) So for example, if you purchased medium brown hair extensions, they’ve already been colored to achieve that color. If you plan on lightening those particular hair extensions you would need to bleach them. Basically, whatever you can do to your own hair you can do with human hair extensions.
Because the hair products have been dyed in the factory with special technology, the hair will be easily fragile if you color the hair again. If you would like to dye them anyway, please color them darker rather than lighter only, because bleaching synthetic hair extensions that have already been processed are extremely harmful for the hair. Therefore, I never recommend bleaching the hair, since the hair is not virgin human hair.
If you are coloring them, I recommend going to a synthetic hair extensions to color them for you, unless you are confident with your own ability to dye them. Always test hair dye on a small weft before coloring the whole set.
Extensions of natural synthetic hair extensions category are made only from natural hair 100% pure and healthy, carefully selected and worked. But in the same time you can choose other extensions with your favorite color.