Answering Frequently Asked Questions

Using DecodeChess

A Decode is an explanation in intuitive language, generated by our unique artificial intelligence algorithms. With a decode you can do two things:

  1. Analyze an entire game and receive explanations for the recommended moves of a chess engine (Stockfish). This only takes about 60 seconds!
  2. Analyze a chess position in-depth to receive a 360° analysis of threats, attacking plans, concepts, piece functionality, good moves, and more.


Within each game, there are usually about 5-10 notable positions to analyze and learn from. Our system helps you find these interesting positions via the game map, which shows you exactly where each side dropped or picked an advantage throughout the game.

DecodeChess is using Stockfish 12 NNUE. and is running on our servers. The depth is usually around 24, but it can change dramatically, depending on the complexity of the position. For example, simple positions can reach a depth of 48.

When clicking on the Decode buttons (Decode Game or Decode Deep), the engine is run on our servers.

The more basic analysis interfaces available in DecodeChess, such as the Game Map and the basic analysis (Fish icon below the board), are running on your browser.

Using DecdeChess only requires an internet connection. Minimal supported screen resolution is 800*600. Browser types/versions: Edge, Firefox 44+, Chrome 47+, Safari 9+, Opera 36+, IOS Safari 8.4+, Android Browser 4.3+ (Android version), Android Chrome 49+.

We no longer support Internet Explorer (IE) because it is out of date and lacks advanced functions that are crucial for running our program.

We use Stockfish 12 NNUE in different areas of DecodeChess.

Please note that the discrepancies between the moves mentioned in Decodes and those showing on the graph (Game info) stem from the fact that the engine is run at different depths and is generally an unstable creature. When clicking on Decode, our servers work harder to find the best line, while the visual graph is run on your side of the server, and thus to prevent slowing down your internet we limit the engine’s depth.

Please also note that the game’s graph keeps updating and will arrive at a more accurate analysis only when this bar stops spinning.

You can upload any game or position in PGN and FEN formats, via the New Game menu that is available at the top left corner of the screen.

DecodeChess App is available on Google Play. Currently the app is not available on Apple store.

DecodeChess is mobile responsive. This means that you can access it via your smartphone, simply with less analysis features, due to the size of the screen.

Available features in mobile mode:

  1. Play against the computer and decode positions as you play.
  2. Setup the board and decode any position you have in mind.
  3. Access your History folder and our Examples folder.
  4. PGN File upload is still available, simply requires you to have it on your mobile device.

Missing features in mobile mode

  1. Our rich tab system (Threats, Good Moves, Plans, Functionality, Concepts)

♦ We recommend using DecodeChess on a big screen for full functionality and an optimal chess analysis experience.

We save each and every decode session, be it through a game you upload, a game against our computer opponent, or any board set up.

In addition, you can search for, tag, and delete games if you wish with our friendly history folder.

DecodeChess is a web-based service. It relies on a proprietary algorithm which requires significant CPU resources to produce its automatic explanations and is therefore available through our servers only. This is actually a big advantage, as you’re not required to install anything on your computer.

At the moment, all your analyses are saved in your online account, but are not available for download/export. We hope to release this feature within a few months.