When your toenail splits in half, will it look normal again after it heals?

Depends on the cause: If the cause of the split in the nail was a traumatic injury, then the nail matrix at the back of the nail could be damaged and this would cause permanent changes to the nail. If the matrix was not involved the nail should grow out without issues. Other reasons for a nail to split would be nutritional or metabolic. These can be resolved with diet and supplements. Check with your foot doctor.

Time will tell: This depends on the degree of trauma causing the nail to split. It may grow back normal, it may grow back deformed. Also, trauma can lead to a nail becoming infected with fungus which will also cause a nail to grow abnormally. Only time will tell how your nail will grow back. It takes approx. 1 year for a great toenail to replace itself, toenails grow approx. 1mm/month.