How it works

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How the analysis works

There are 3 servers that can analyze your .SGF files.

  • “Beginner” server – Free – For double-digit Kyus.
  • “SDK” server – $0.25 per analysis – For single-digit Kyus.
  • “Dan” server – $0.25 per analysis – For Dans.
  • Note: All servers are free every weekend.

Step 1 – Upload an .SGF file of a game

Select a server and upload the .SGF file of your game. If you include an email, you’ll be emailed once the analysis is complete along with the link to download the analysis.
Note: Rosy Stein currently only supports 19×19 games, although we do plan to expand our service to 9×9 and 13×13 soon.





 Step 2 – Download the analyzed .SGF file

If you provided an email: You will be emailed when the analysis has been completed, and provided with a direct link to download the analyzed .SGF.

If you didn’t provide an email: You will need to visit the server page which you used, and enter the 5-character code which you received when you uploaded your .SGF.




Step 3 – Review

The .SGF can be viewed with an .SGF application. For windows, I recommend Drago and for Android I recommend Gobandroid.

When the analyzer finds mistakes in your play, it will branch out, providing suggestive variations which it would play instead (seen left).

It also provides some information in the comments on the move, for example how significant your mistake was.

Additionally, when it finds a mistake, it draws letters on the board representing the moves it would play instead with A being its most preferred move, working its way down to F being its least preferred move.

The triangle shown represents the move which you (or your opponent) played instead.



  • For example .SGFs, please see our Gallery.
    • The further the game is from even, the bigger the mistakes have to be for the bot to critique them, as a 3% mistake when black has a 95% chance to win wouldn’t matter as much.
    • The bot is less accurate when analyzing handicap games.
    • The bot is less accurate when the komi is set to a strange value.