Professional ranks go from 1 dan to 9 dan, with 9 dan being strongest.
In Japan, the traditional pro handicapping made a difference of three ranks per stone. However, with the new (post-WWII) pro rankings, there seems to be a two-stone difference between active 9-dans and shodans, which translates to about 1/4 stone per rank.
- Professional rank histograms
- Rank - amateur and professional
- A One-Dan Pro may be Stronger than a Nine-Dan Pro
- Promotion systems
- World Ranking
- The rank progression of Japanese pros
 This estimate of the difference between 9p and 1p is only approximate. First, there is a range of strengths within 9p simply because there are no higher ranks. It can be argued that top title holders such as Cho Chikun in his prime are significantly stronger than the average 9p, possibly even two ranks stronger. And, too, there is a range of strengths within 1p, for example some pros who qualified as 1p never advanced beyond that rank and often lose to run of the mill amateurs,and some 1p players advance very rapidly to 2p. Without an official pro handicap system in use, with handicaps determined through actual tournament play, it doesn't make much sense to talk about pro handicaps for modern pros.