About 2 years for a blue belt, 4 for a purple, 6 for a brown, and 8 years for a black belt. However, results will vary! This is just an estimate based on an individual who consistently trains 3-5 times per week. The time could differ me more if you train sporadically, or less if you train 24/7. Read 'How Long Does It Take to Get Each Belt' for more.
It should be noted that even though it takes about 2 years to get your blue belt. You will likely be substantially better at grappling after about six months. Most people don't grapple at all and even a little bit of jiu-Jistu will make a lot of difference.
White: 0 Years (0 Hours)
Blue: 1-3 Years (300-900 Hours)
Purple: 3-5 Years (900-1600 Hours)
Brown: 5-8 Years (1600-2500 Hours)
Black: 8-12 Years (2500-3700 Hours)
What is a gi?
A gi is a lightweight, loose-fitting garment consisting of pants, a jacket, and a belt to tie the jacket.
How often should I train BJJ?
For beginners, 3 times per week is a good starting point.