.CK2

.CK2 file extension

This is the basic program to work with .CK2 extension

ChessBase Light 2007

ChessBase Light 2007 ChessBase Theme classification

The program works with the following extensions: cto, cbp, pgi, cbt, pgn, cbv, cbz, cib, cit, ck1, cbs, ck2, cko, ck3, cba, ckn, cp1, cbb, cp2, cbc, cp3, cbe, cpn, cbf, cpo, ctb, cbh, ctg, cbm and cbgi

.CK2 extension is also supported by the following programs:

ChessBase 9

ChessBase 9 ChessBase Theme classification

ChessBase

ChessBase ChessBase Theme classification

ChessBase 13 is a personal, stand-alone chess database.
ChessBase Reader

ChessBase Reader ChessBase Theme classification

Open chess games database files and play through the games.