The time it takes for burn pain to go away depends on the severity of the burn.
If you have a small burn then it may only take a few hours to 24 hours for the burn pain to go away.
If you have a more severe burn that requires medical attention then you may experience burn pain for a few days to even a few weeks.
If you happened to just burn your skin slightly and do not require medical treatment then the burn pain should go away within a few hours to a day at most.
But sometimes the burn pain may last another day or so.
If the burn is getting more painful or it seems to be getting infected then see a doctor or go to the emergency room or urgent care.
Less severe burns should heal within a few weeks but more severe burns may take a month or two to fully heal.