Choose a small strand of hair and burn it. If the hair is 100% human, it smells like a barbecue and the ashes can be twisted into powder; if not, it smells like plastic and the ashes will stay as a caking.
That is very obvious: with the same style and length, Human hair wigs are much more expensive than synthetic ones. Therefore, If your human hair wig is relatively cheap, you may need to consider whether it's blended with synthetic fiber or the hair that collected to make this wig is not of a healthy quality.
Use a flat iron to heat the hair. If the hair can be heated at 220 degrees without a paste, it is real human hair. Well, a small strand of hair is enough for the test.