In 2013 Aesopian published the results of his gi survey. We finally had definitive numbers we could point to in terms of how long it took to get to each rank on average. Those numbers have been the ones the online BJJ community has seemed to lean on for the last seven years to answer that question. BeltChecker has its own stats now too. Unfortunately, I don’t have the raw data for either, so I can’t do a proper evaluation, but here’s a table comparing the two sources:
Aesopian | Belt Checker | BC # | Difference | |
White -> Blue | ~ 2 years | 2y 11m 6d | >2679 | ~11 months |
Blue -> Purple | ~3 years | 3y 1m 24d | 1727 | 0 |
Purple -> Brown | ~2.5 years | 3y 1m 10d | 1141 | ~6 months |
Brown -> Black | ~2.5 years | 2y 10m 8d | 710 | ~4 months |
White -> Black | ~10 years | 12y 0m 9d | 710 | ~2 years |
A couple of notes
- Aesopian didn’t give any hard numbers, so these are roughly the numbers from looking really hard at his graphs and what numbers he does say.
- The number of BeltChecker users counted are me manually adding the number of verified folks at or above the given belt at the time I pulled these numbers. I included it because knowing the sample size matters. We don’t have it for the Aesopian data unfortunately. Also, the white to blue could also be misleading as BeltChecker has it as time as a white belt, which could include the youth belts they have (grey, yellow, orange, green). There are only 36 individuals with youth belts on BeltChecker though, so I don’t think it could have skewed the data too much if at all.
If we add up the BC data for individual belts, we’d expect the white to black average to look something like 11 years, 11 months, which is pretty close to the 12 years calculated from black belt profiles, so I think this pool of folks is at least internally consistent with how long it seems to take. So, at least in 2020, it looks like it now takes around 12 years to get a black belt. It would be interesting to get the raw data to see if the average has just increased by 2 years in the last 7 years, or if there’s something in the data that would explain it. Notably, I’d love to see if there are differences in the BC data between folks promoted as of 2013 and the folks promoted in the last 7 years.
Even if you think belts don’t matter – this is an interesting thing to evaluate as a coach. How long on average do students take to get a given belt under you? Does that change over time? How do they compare to averages, including as averages change over time?