A new analysis tool that explains critical moments in your games and makes tactics impossible to miss
Over the past few months, I’ve been hard at work on building a Chess Coach, adding new features, improving accuracy, and rethinking how we can better spot and explain the hidden moments that decide your chess games.
Try it now on your own games at https://app.chesscoach.dev/
Today, I’m excited to share the biggest set of improvements yet.
Why I am building Chess Coach
Every chess player knows the frustration: you finish a game, load an engine, and get a wall of evals that doesn’t really tell you why you lost or what you could have done differently. I wanted to change that by building a tool that doesn’t just evaluate, but actually teaches you. One that works instantly, runs anywhere, and makes sense to players at every level.
The latest upgrades
Here’s what’s new and how it changes your analysis experience.
Lightning-fast local analysis
The app now runs a local Stockfish engine right in your browser. That means no more waiting for server responses and your moves are analyzed instantly. The whole pipeline has been rebuilt to make every click feel responsive for your entire game.
Smarter AI with GPT-5
Critical Moments detection is now powered by GPT-5 the best model yet for chess understanding. This upgrade means:
- More accurate move evaluations
- Deeper and context-aware insights
- Better identification of the moments that truly mattered
Instead of just telling you “this move was a blunder,” it now explains why, using concepts you can apply in your next game.
For example, in my game below as white, I played Rec1 whether the better move was Rac1. The explanation discusses the black bishop on g7 targeting the Rook a1 in the actual game. The explanation is a great start and will only get better over time as I ground the LLM further in chess knowledge.
Tactical Analysis: never miss a threat again
This one came directly from user feedback on our Suggestions page. The new Tactical Analysis mode instantly highlights:
- Forks
- Pins
- Skewers
- Discovered attacks
It also shows whether each piece is attacked or defended — so you can see the tactical landscape at a glance. Whether you’re learning your first motifs or reviewing master games, this view makes the invisible visible.
For the same position it indicates that black bishop on g7 is an hidden attacker and shows that black pawn on c7 is vulnerable
Another example showing some forks and pins.
A cleaner, mobile-first experience
The entire interface has been redesigned for mobile. You can now review games, jump between critical moments, and toggle features with a cleaner, more intuitive layout that works just as well on your phone as it does on a desktop.
Your ideas in action
This Chess Coach isn’t built in isolation. It’s shaped by the people who use it. With the new Suggestions page, you can:
- Submit new feature requests.
- Upvote ideas from other players.
- See what’s in progress.
Tactical Analysis exists today because users asked for it — so if there’s something you wish the app did, please do suggest away.
Built for players to improve
At its core the Chess Coach goal is simple: To help players improve.
All these updates are live right now. Try them out at app.chesscoach.dev and let me know what you think. Your feedback is what keeps this project growing.