KKBJ-FM (103.7 FM), known on-air as "Mix 103.7", is a radio station based in Bemidji, Minnesota, that airs a Top 40 (CHR) format.

The station previously had a Top 40 (CHR) format as B-103, "Today's Best Music" and flipped to adult contemporary as Mix 103.7 in 1994, after being sold to RP Broadcasting.

The station switched to hot adult contemporary format a few years later.

In recent years, the station began evolving to a Top 40 (CHR).

The station plays the Daily Download with Carson Daly every Saturday morning and Backtrax USA and the American Top 40 with Ryan Seacrest every Sunday.