How long does it take for a sun burn to go away?

2-4 wks: You can't speed up healing--that is your natural ability. U heal faster when u r young and still growing. As u get older, this slows down. Keep burn-area clean and dry, and minimize re-exposure to sun/heat, the skin can usually replace itself/heal in about 3-4 wks. Be good, be sensible. Sunscreen use reduces skin cancer. If severe, consult doc. Good luck.