The Fritz Powerbook 2005 is an openings book and database that will run with Fritz or any Fritz compatible engine (Shredder, Junior, Tiger, Nimzo, etc.). You can also use it in ChessBase 7, 8 or 9 to conduct openings training and hone your repertoire.

The Fritz Powerbook 2005 contains 20 million openings positions, which were derived from 1 Million high-class tournament games. Together with each position all relevant information is stored: all moves that were played in the position, by players of what average rating, with what success and performance results. The games from which the Fritz Powerbook 2005 was derived are also included on the CD. This means that in any position of the opening tree, you can load and replay the games in which the position occurred.

The Fritz Powerbook 2005 represents the state of the art of current opening theory. It can be used to discover exciting new lines (e.g. never before played transpositions) and practice them against Fritz.

Fritz 8, Fritz 7, Fritz 6 and all other ChessBase engines under the Fritz interface can use the PowerBook 2005 as opening book, making the opening play of the programs more topical, versatile and entertaining.

Review by Steve Lopez
What is an openings book?


In the initial phase of a game, the program plays out of an “openings book”. This can consist of millions of openings positions, and for each of these, the program has full information on which moves were played, how often and with what results. The program stores its own experience with openings variations it has played. It learns from success and defeat.

The openings book is called the “tree” as the branching variations in the opening resemble the structure of a tree. The files that make up a tree are pretty large. The program requires about 80 bytes to store a position and all the information associated with it. You can leave the files on the program CD. However, in this case, the program will not be able to modify the book as it plays games (i.e., it cannot learn). Thus, it is advisable to copy them to your hard disk.

Some things to note:

Using the book window

In Fritz and ChessBase you consult the openings book by clicking on the “Openings book” tab at the top of the notation window.

This is what you see in the openings book tree:

Display options

Right-click the book window to configure the display, i.e. enable or disable a number of elements of the tree window. These are the most interesting:


Unplayed transpositions, retro moves

The moves in grey (8...h6 and 8...Nc6) have never been played in the current position, but lead to positions that are part of openings theory.

8.0-0 and 8.Bd3-e2 are moves that lead to the current position.

How to navigate the tree

Right-click the book window to execute a number of commands, e.g.:
  • retrieve the game in which the curren position occurred;
  • sort the moves
  • prune or delete the tree
  • etc.


Right-click a move to
  • annotate it (with !, ?, +–, etc.);
  • make it the main move in the current position;
  • instruct Fritz never to play this in tournament mode;
  • modifiy the weighting manually;
  • delete the move or variation

Installing Powerbook 2004

In Fritz you click Edit – Openings book – Copy tree to hard disk. This will copy an openings tree from the CD to your hard disk, making access faster. Doing this also allows the program to learn from the games it has played and by reading databases.

Importing games to the openings book

Click Edit – Openings book – Import games. This very powerful function allows you to extend the openings book very quickly and with no technical hassle. You can, for instance, import all the games of the latest ChessBase Magazine, or only those from the lines you play. The games will be merged to a tree of positions. The length of the variations ist limited in two different ways: You can specify that every variation should be “n” moves long; or, more sensiblly, you can limit the variations relative to the ECO classification. This results in long variations for theoretical main lines (ECO classification position found late in the game) and short variations for side lines (i.e., early deviations).