Generate sudoku puzzles in five difficulty levels, with a solver and an analyzer


Our rating: 


Pros & Cons:

Five different and configurable difficulty levels, includes solver and analyzer, summary of solving techniques and solution paths, redo/undo steps, show candidates and invalid values, next vague or concrete hints, cross platforms.

Our Review:

HoDoKu is an open source program and runs with Java on Windows, Linux or Mac. It allows you to generate sudoku puzzles in five different and configurable difficulty levels. It also includes a solver and an analyzer to help you solve the puzzles.

While playing the game, you can select to view a summary of solving techniques and the solution paths. When you click on a solution path, it highlights the steps on the corresponding grid to help you analyze the game. You can also opt for a practising mode, tick one or more techniques to be included in a new puzzle. All these features make HoDoKu not only a game to play but also a nice tool for learning and honing your skills in the game as well.

Other useful features include redo/undo steps, show candidates and invalid values, next vague or concrete hints and more. Puzzles can be saved in a proprietary hsol format, SimpleSudoku (ss) format, or a pure text file.

HoDoKu was reviewed by on


I think your statement "no import and export of files are supported" in relation to HoDoKu is wrong. Yes, .hsol is its native "save game" format. However, it does allow to reproduce puzzles in, afaik, a universally accepted format. That is, a comma-separated value file. Available via Edit > Copy...
Usually, Copy Candidates works best. The Library format preserves the difference between Givens and set Values too, in case that might useful. There's a Copy Step (Hint) in there somewhere as well, iirc.

Sadly, this program is no longer under development by its author. But, with a little help from friends of HoDoKu, I did get this done https://github.com/1to9only/HoDoKu/releases/tag/2.2.2

Thanks CCV for the kind comments. This feature has now been updated in the review.