What Is Stockfish?

Chess engine

Stockfish is a program that analyzes chess positions and chooses very strong moves. It is used for computer play, game analysis, and checking variations.

Position evaluation

The engine returns an evaluation in centipawns or mate in a specific number of moves. A positive score usually favors White, while a negative score favors Black.

Openings

In this app, first moves can come from an opening book, and only after leaving known positions does Stockfish take over.

Why does the engine see more?

Stockfish checks a huge number of variations and evaluates positions through many features: king safety, piece activity, pawn structure, material, and potential threats. Humans usually do not calculate that broadly, so the engine quickly finds moves that may look unnatural at first.

Training is not about playing like a computer. A better goal is to understand which position features the engine valued most and how to notice them next time without help.

How to use it sensibly

First try to choose the best move and plan yourself. Only then compare your answer with Stockfish. This approach trains evaluation rather than only checking ready-made solutions.

If the difference between your move and the engine move is small, do not overanalyze it. Focus on big evaluation drops, mates, simple material losses, and positions where you did not understand the plan.