How long before judo can be used in self defence?

no one can answer when you can use any style for self defense with out knowing how many hours per week you train and how your instructure teachs they are all difernt but judo rocks for self defense and at your size to be good at self defenses if you have great muscle memory and personal memory youll looking at two belts up before you i would consider you good at self defense that depending on everything can take anywere from 12months to two years but depending on your natural skill you could be good as you sit right now hince why i have trouble being honest in this question with the information givin hope this helps