Go Baduk Weiqi Igo Rankings

"Kyu" is pronounced "Q" (the name of the letter).
"Dan" is pronounced just as you would except, like the name Dan.

The lowest possible rank is 30 kyu, which is what you start as when you are first introduced to the game. As you improve, you work your way up to 1 kyu.

When you increase 1 rank above 1 kyu, you become 1 dan. You can then increase up to 7 dan. (or 9, if you're in the US.)

Those are the amateur rankings. There are also professional dans, which start at 1 dan and go to 9 dan. A 1 dan professional could be considered 1 rank about the best amateur dan. However, the difference between professional dans is much lower than between the amateur rankings. Between any two professionals, there is rarely more than a 2-3 stone difference.

There are no professional players from the U.S. because we don't have a professional association. Japan, China, Korea, and Taiwan all have professional associations: players in these associations are paid to play in go tournaments. Professional players play Go as their career, like a professional athlete.
This is the reason that U.S. amateur dan rankings go higher than those in Japan.

Korean amateur rankings are measured in "gups", also on a decreasing scale.