The time it will take for your angular cheilitis to heal up depends on how severe the angular cheilitis is.
But in most cases the angular cheilitis will fully heal on it's own and go away within 3 weeks at most but sometimes it may last as long as 4 weeks.
You can help speed up the healing process of angular cheilitis by applying some coconut oil or petroleum jelly to the angular cheilitis and it will help heal it and make it feel better as well.
The coconut oil or petroleum jelly will also help protect the angular cheilitis from saliva which can irritate it and make it worse or take longer to heal.
Applying some Lip Balm to the angular cheilitis can also help with the healing process or applying some moisturizing cream to the area.