What you get back
- The best move in standard notation, drawn on the board as an arrow.
- The evaluation after that move, so you know whether it wins, holds, or merely loses slowly.
- The runner-up moves, which are often the more useful part — if the second choice is nearly as good, the position has options; if it drops off a cliff, the best move is the only move.
The engine tells you what, not why
An engine returns a move and a number. It will not tell you that the move works because it takes the open file, or that your position went wrong nine moves earlier. That gap is the reason engine output alone rarely improves anyone’s play — we wrote about it in why Stockfish shows the best move but not the plan.
One position is a sample; the game is the story
Checking a single position is useful when you already know which moment mattered. Usually you don’t — the losing decision is rarely the move that felt wrong. Run a full game review instead: import the game from Chess.com or Lichess and every move gets graded, so the moments worth studying find you.
A note on fair play
Use this after the game, not during one. Every major chess site treats engine assistance in a live rated game as cheating, and detection is better than most players assume. Studying a finished position is how engines are meant to help.
Frequently asked questions
How does the next move calculator work?
It runs Stockfish 18 — the same engine used by the major chess sites — directly in your browser. The engine searches the position you paste and reports the move with the highest evaluation, along with the next-best candidates. Nothing is sent to a server; the search happens on your own machine.
What is a FEN and where do I get one?
FEN is a one-line text description of a chess position: piece placement, whose turn it is, castling rights, and the move counters. Chess.com, Lichess, and most board editors let you copy the FEN of any position from the analysis screen.
What do the evaluation numbers mean?
A number like +1.24 means the side to move is ahead by about 1.24 pawns of material-equivalent advantage. Positive favours White, negative favours Black. "M3" means forced mate in three moves.
Is using this during a live game cheating?
Yes. Consulting an engine while a rated game is in progress is against the rules of every major chess site and will get an account closed. This tool is for studying positions after the game, or for working through a puzzle or a study position.