How to correctly use an analysis engine
Analysis engines like Stockfish are incredibly powerful tools, but using them incorrectly can be counterproductive. Learning to interpret their evaluations and suggestions is a skill in itself. The engine tells you what is objectively better, but that does not always mean it is the best option for you. Understanding this distinction is key to using the engine as a learning tool and not as a crutch.
Analyzing first without engine
Before turning on the engine, spend time analyzing the game yourself. Identify the moments that seemed critical to you, the moves where you hesitated, the mistakes you think you made. This exercise trains your evaluation ability. If you always depend on the engine, you never develop your own judgment.
If you jump straight to the engine, you never develop your own judgment. You end up depending on the computer for everything, which does not help you during games when you do not have access to the engine. The goal of analysis is to improve your understanding, not to get the right answers from an external authority.
An effective technique is to write your conclusions before consulting the engine. Note the positions that seemed critical, what alternative moves you considered, and why you chose what you chose. Then, compare with the engine. This comparison is where real learning occurs.
Understanding evaluations
The engine evaluation is measured in centipawns (cp), where 100 centipawns equal one pawn of advantage. An evaluation of +150 means white has an advantage equivalent to approximately one and a half pawns. Evaluations close to zero (between -50 and +50) generally indicate practical equality.
Do not obsess over small evaluation differences. The difference between +30 and +50 is rarely significant for a human; both positions are approximately equal from a practical perspective. Focus on large evaluation changes (100+ centipawns), which indicate real mistakes that change the character of the position.
Tools like Nexa chess classify errors according to their centipawn impact: inaccuracies (minor losses), mistakes (moderate losses of approximately 100-300 cp), and blunders (major losses of 300+ cp, often equivalent to a piece). This classification helps you prioritize which errors to study first.
Beyond the best move
The engine always shows the best move, but that is not the most important thing. The important thing is to understand why your move was worse. What did you not see? What tactical or strategic idea did you ignore? The engine gives you the answer, but you must do the work of understanding.
Also look at the other moves the engine considers. Often there are several moves with similar evaluation, and understanding why they all work gives you more flexibility in similar positions. If the engine says both Nf3 and Ne2 are equally good, understanding why teaches you something about the position.
When the engine suggests a move that seems strange to you, do not dismiss it as "computer stuff." Investigate why it works. You will often discover an idea your intuition did not capture but which, once understood, can improve your play. Engine surprises are learning opportunities.
Engine limitations
Engines are excellent for tactics and short-term positional evaluation, but they do not understand strategic concepts the same way humans do. An evaluation of 0.00 does not mean the position is easy to play for both sides. Some equal positions are much harder to play for one side than the other.
Some positions are objectively equal but practically very difficult to defend. The engine does not distinguish between these and truly balanced positions. Your experience and human judgment are still necessary to understand the practical difficulty of a position.
The engine also does not understand game psychology. A move that "complicates" the position may be practically superior even though the engine evaluates it the same as a simpler move. Against an opponent who plays poorly in complicated positions, complicating has value even if the engine does not reflect it.
Phase analysis with engine
Modern tools like Nexa chess not only analyze move by move, but separate analysis by phases: opening, middlegame, and endgame. This gives you more actionable information. If your opening Elo is 1500 but your endgame Elo is 1200, you know exactly where to focus your study.
Phase analysis uses specific cut-off points. Typically, the opening ends around move 13, the endgame begins when few major pieces remain on the board (generally 6 or fewer among queens, rooks, bishops, and knights). The engine evaluates your performance in each phase separately.
This type of analysis reveals patterns that game-by-game analysis does not show. Perhaps you consistently gain advantage in the opening but lose it in the middlegame. Or perhaps your endgames are solid but you enter them at a disadvantage. This high-level information guides your study plan.
Integrating the engine into your study routine
The engine should be part of your study routine, not the center of it. An effective study session might include: 10 minutes of your own analysis, 15 minutes of engine review, and 5 minutes of noting the main lessons. The exact proportion depends on your level and time availability.
Weekly tracking of your metrics allows you to measure if your engine use is producing results. If after a month of regular analysis your errors per game decrease, your method is working. If there is no improvement, perhaps you need to change how you use the engine or what aspects you focus on.
Finally, remember that the engine is a tool, not a teacher. It does not tell you what to study or how to improve; it only shows you where you went wrong. The interpretation of that information, and the decision of what to do with it, remains your responsibility. The player who uses the engine intelligently improves; the one who only consults it without reflection learns little.