What is the lenght of a baseball court?

First of all, it's not a "baseballcourt," but instead, a "Baseball field."

Basefield fields are most commonly identifield by the size of the diamond, or the distance betwen the bases. Major League Baseball, college and High School play on a 90-foot diamond. Smaller fields, 60-foot, 70-fot and 80-foot diamonds are used by younger age groups.