How long does it take a broken blood vessel in the eye to fully heal?

2-3 weeks: Even a single drop of blood with a subconjunctival hemorrhage can have a dramatic appearance. Just like a bruise, it usually takes 10-21 days to resolve as the blood breaks down. Be sure to use some artificial tears for irritation and if the hemorrhage is accompanied by any other symptoms, see your ophthalmologist.

Variable: Usually a few weeks as the blood is broken down (changes colors and fades) and eventually completely reabsorbed from a conjunctival hemorrhage. Sometimes the heme gets larger before going away.