Answers.Body: <p>This kind of thing isn't done by hand, but by computer programs. It is not too difficult to run some program on a game database and extract all positions suitable for a tactical exercise.
  Sorting them by difficulty will be done over time, when statistics accumulate how often they are solved correctly.</p>
  
  <p>Of course there are tactical exercise positions out there, but I don't know any that are already sorted by motif or difficulty. This is a site with 10,000 tactical positions (surely mined by a computer):</p>
  
  <p><a href="http://www.wtharvey.com" rel="nofollow">http://www.wtharvey.com</a></p>
  
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Answers.CreationDate: 2014-12-31T16:58:04.003Z
Answers.Text: I do see that you could mine some of them using ChessBase, and that you could set up difficulty using clever tricks, like the strength of the victom. Motif analysis seems much harder... I suppose I could write something that detects the presence of elements like pins and discovered checks. Sounds sort of interesting actually... But if it was possible to not do this work, that would be better.
Answers.UserDisplayName: Brian MacKay
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Answers.CreationDate: 2014-12-31T16:11:01.350Z
Answers.LastActivityDate: 2014-12-31T17:41:08.447Z
Answers.LastEditDate: 2014-12-31T17:41:08.447Z
Answers.UserDisplayName: BlindKungFuMaster
Answers.Body: <p>This is one, <a href="http://dejascacchi.altervista.org/exercises.htm" rel="nofollow">http://dejascacchi.altervista.org/exercises.htm</a>
  Thus are from real games.</p>
  
  <p>Also the online chess site, chesstempo.com, has problems with an elo rating (calculated as an accumulated result of the success rate of solving by other players of the same site, and it has rankings too). Also has endings problems. All problems seem to be computer generated (for analysis of games).</p>
  
  <p>Also the now death spaniard magazine, "Ocho x Ocho" (from 80s - 90s) had in each number problems classified by 5 levels (Google "ocho x ocho revista de ajedrez").</p>
  
  <p>The books from Franc Loheac Ammoun, available in several languages, for example <a href="http://www.amazon.fr/Testez-vous-aux-%C3%A9checs-Frank-Loh%C3%A9ac-Ammoun/dp/2501014006" rel="nofollow">http://www.amazon.fr/Testez-vous-aux-%C3%A9checs-Frank-Loh%C3%A9ac-Ammoun/dp/2501014006</a>
  or <a href="http://rads.stackoverflow.com/amzn/click/8480192410" rel="nofollow">http://www.amazon.com/Compruebe-Nivel-Ajedrez-Desarrolle-Razonamiento/dp/8480192410/ref=sr_1_2?ie=UTF8&amp;qid=1421005140&amp;sr=8-2&amp;keywords=Frank-Loh%C3%A9ac-Ammoun%2F</a>
  Put you to solve tactical problems and then calculates your rating.</p>
  
  <p>There are other I forgot, will update it here as I remember...</p>
  
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Answers.CreationDate: 2015-01-11T19:36:06.837Z
Answers.LastActivityDate: 2015-01-11T19:36:06.837Z
Answers.UserDisplayName: Fernando Gonzalez Sanchez
Body: <p>I'm toying with the idea of building a tactical training tool. For my idea to work, I need positions that are categorized by motif and difficulty.</p>
  <p>A lot of tools seem to have this, and I doubt they're all building up thousands of positions by hand. So there must be databases out there, available for use (free or commercial are both okay), and probably already tagged. Any idea where to start looking?</p>
  
Tags: <tactics><training><database><programming>
Title: Where can I find databases of tactical problems, categorized and ranked by difficulty?
ThreadText: # Where can I find databases of tactical problems, categorized and ranked by difficulty?
  
  (Asked by: username_0 on 2014-12-31)
  
  I'm toying with the idea of building a tactical training tool. For my idea to work, I need positions that are categorized by motif and difficulty.
  
  A lot of tools seem to have this, and I doubt they're all building up thousands of positions by hand. So there must be databases out there, available for use (free or commercial are both okay), and probably already tagged. Any idea where to start looking?
  
  **Tags:** tactics, training, database, programming
  
  
  ---
  
  ## 2 answers
  
  ### Answer by username_1 on 2014-12-31. Score: 3 | Accepted answer
  
  This kind of thing isn't done by hand, but by computer programs. It is not too difficult to run some program on a game database and extract all positions suitable for a tactical exercise.
  Sorting them by difficulty will be done over time, when statistics accumulate how often they are solved correctly.
  
  Of course there are tactical exercise positions out there, but I don't know any that are already sorted by motif or difficulty. This is a site with 10,000 tactical positions (surely mined by a computer):
  
  <http://www.wtharvey.com>
  
  > **Comments:**
  > **username_0**: I do see that you could mine some of them using ChessBase, and that you could set up difficulty using clever tricks, like the strength of the victom. Motif analysis seems much harder... I suppose I could write something that detects the presence of elements like pins and discovered checks. Sounds sort of interesting actually... But if it was possible to not do this work, that would be better.  
  
  ---
  
  ### Answer by username_2 on 2015-01-11. Score: 2
  
  This is one, <http://dejascacchi.altervista.org/exercises.htm>
  Thus are from real games.
  
  Also the online chess site, chesstempo.com, has problems with an elo rating (calculated as an accumulated result of the success rate of solving by other players of the same site, and it has rankings too). Also has endings problems. All problems seem to be computer generated (for analysis of games).
  
  Also the now death spaniard magazine, "Ocho x Ocho" (from 80s - 90s) had in each number problems classified by 5 levels (Google "ocho x ocho revista de ajedrez").
  
  The books from Franc Loheac Ammoun, available in several languages, for example <http://www.amazon.fr/Testez-vous-aux-%C3%A9checs-Frank-Loh%C3%A9ac-Ammoun/dp/2501014006>
  or [http://www.amazon.com/Compruebe-Nivel-Ajedrez-Desarrolle-Razonamiento/dp/8480192410/ref=sr\_1\_2?ie=UTF8&qid=1421005140&sr=8-2&keywords=Frank-Loh%C3%A9ac-Ammoun%2F](http://rads.stackoverflow.com/amzn/click/8480192410)
  Put you to solve tactical problems and then calculates your rating.
  
  There are other I forgot, will update it here as I remember...
  
  
  ---
  
  