From OpenStreetMap Wiki
|amenity = dojo|
|A formal training place for any of the Japanese do arts.|
|Used on these elements|
|Status: in use|
|Tools for this tag|
According to Wikipedia, “a  For OpenStreetMap only physical dojos as dojo buildings, halls, rooms and/or organizations are relevant.is a Japanese term which ... can refer to a formal training place for any of the Japanese do arts but typically it is considered the formal gathering place for students of any Japanese martial arts style to conduct training, examinations and other related encounters.”
Tags to use in combination
- sport=* such as aikido, judo, kendo, karate, etc.
- building=yes or building=school if it is a dojo in a school building
- level=* - for dojos on a specific floor of a building
- operator=* in case it's part of a larger chain of dojos
- Article in Wikipedia at 30 October 2012.