There are temporary tattoos that look like real ink and last for up to 3 weeks. You apply Inkbox tattoos by holding them firmly in place for 15 minutes while they sink into the top layer of your skin, which reacts to the organic formula and darkens within 24 hours. Your skin’s natural regeneration time is about 2 to 3 weeks, so that’s how long the tattoo stays in your epidermis. Source