Currently I am using Tarrasch for GUI and Rybka 2.3.2a as the engine. With that, I am able to kibitzing every position in the game and check for any blunder. So basically this is what I always did:

  • Record all of the moves with Tarrasch and then save it in PGN format.
  • Kibitzing with Rybka from the 1st move, check the evaluation.
  • Continue to the next move, kibitzing again, etc.

Is there any faster way than checking every position one by one like this?


7 Answers 7


Lichess.org has a free browser-based game analysis tool that allows you to copy and paste your PGN file for online analysis.

It's powered by Stockfish, and the analysis automatically:

  • Annotates the game with inaccuracies, mistakes, and blunders.
  • Graphs the game with an interactive move-by-move advantage chart (see below).
  • Suggests improved lines.
  • Names the opening.

Game analysis on lichess.org

Lichess game analysis

It doesn't beat going through your games with your opponent and a good instructor, but it's a very useful free tool, and you don't need to install any software to run it.

The developer of lichess.org also has a blog post about Stockfish and the analysis tool.

  • FYI, it doesn't work well with older operating systems, such as XP. This was an intentional change. Commented Jul 7, 2019 at 14:52

You could try

PGN ChessBook

Which is a free app that has some good automatic blunder-check / game-annotation features.

It can find blunders, then automatically annotate the game by inserting variations and (optionally) adding comments to the blunder moves, which can then be printed out, as described in this video

How to find and print out game blunders using PGN ChessBook

I hope this helps someone.


I realise that this is a couple of years old, but in case anyone reaches this page you can use SCID analysis, there is an icon at the bottom of the analysis window called "annotate" and this will loop over each move with whatever chess engine you configure, and label the mistakes, blunders etc.


I have set up a small, free app just for this occasion. It's called chess blunder trainer, and it analyzes your own games to identify your blunder moves. Then, you can replay the position in puzzle forum to find better moves and hopefully improve your skills :)

You can find it on Google Play Store via https://play.google.com/store/apps/details?id=com.cbt.chess_blunder_trainer

Chess Blunder Trainer App

You can find out more about the app here: www.chessblundertrainer.com


I know this is not a programming stack exchange, but... If you have any interest in programming, this would be a perfect task for a simple program and a great learning experience. It could be done in most any programming language.

You can take your PGN separate the moves, input them into a chess engine and give it a certain amount of time to analyze each move. Parse the evaluation for each move and store it. Then loop through the moves, calculate the difference in evaluation from the previous move and classify it as a "blunder" if the evaluation changes more than a defined threshold (1 pt, 2 pts, 3 pts up to you) or perhaps a defined percentage (You may have to consider when the eval is like +10 that it can vary more wildly and maybe omit those scenarios).

If you did this, you could give it a entire list of games, come back in a while and see a list of possible blunders. Otherwise, I think you are left doing it by hand.

  • That's a cool idea. Do you have any tips for me about writing the program with Python?
    – wisnuops
    Commented Jun 4, 2014 at 17:08
  • @wisnuops Not exact tips, I'd start by understanding the format of everything. You know PGN is your input, figure out how to separate each game and each move. Chess engines use UCI communication interface I think, You'd probably start the process in python and grab it's standard input/output. Write the moves, wait X time, grab evaluation. For Python, you need to research launching a process (chess engine), getting its standard in and out, parsing text, writing text files. Build it step by step, test each part, put them together. Post problems you have on stackoverflow.com =)
    – Alan
    Commented Jun 4, 2014 at 18:06
  • @wisnuops I think the harder part of the problem is, given a set of moves and position evaluations, what is a blunder? What's the difference between your opponent's brilliancy and your blunder? Obviousness? I think you'll likely get a list of potential blunders unless you create a more sophisticated approach then comparing evals before/after. A blunder for a master may be nothing to a novice.
    – Alan
    Commented Jun 4, 2014 at 18:10

[EDIT]: Blunder checking is available now. https://www.chess.com/forum/view/chess-equipment/smallfish---free-chess-ios-app

If you have iOS, please take a look at SmallFish. SmallFish has a 64 bits Stockfish engine, which means it's stronger than Droidfish (it's 32 bits). The app has a graph for evaluation.

enter image description here


If you have an Android device, you can try a new app called "Analyze your games" that reads every move and compares it with the best moves calculated by Stockfish. It also finds blunders and missed tactics.

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