Question 1

Where can I check if my chess opponent was using a bot?

Accepted Answer

Right here. Paste the PGN of any chess game and the fair-play analyzer runs a deep engine analysis on every move to measure how closely each player matched computer-perfect play. You get a risk score from 0 to 100 for both sides, with a breakdown showing engine agreement rates, centipawn loss, accuracy consistency, and the specific moves that looked most suspicious. It runs entirely in your browser - no upload needed.

Question 2

How do I copy my game from chess.com to check for cheating?

Accepted Answer

On chess.com, open the game you want to check, click the share or download button, and copy the PGN text. Come here, paste it into the input box, and hit Run Analysis. The analyzer reads standard PGN from chess.com, Lichess, or any platform. Within minutes you get a full fair-play report with risk scores, suspicious move highlights, and an interactive board review.

Question 3

How does a chess bot detector actually work?

Accepted Answer

The analyzer replays every move of the game and compares each decision against a strong chess engine running at depth 14 or higher. It measures centipawn loss per move, how often each player picked the engine top choice, how consistent their accuracy was, and whether they played like an engine specifically in critical high-pressure positions where humans normally struggle. All of these signals feed into a weighted formula that produces a risk score.

Question 4

What does the risk score mean in chess cheating detection?

Accepted Answer

The risk score ranges from 0 to 100. Scores under 35 indicate very likely human play with natural mistakes and variation. Scores between 35 and 55 show mostly human play with some strong stretches. Scores from 55 to 70 suggest engine-like streaks that could be talent or could be concerning. Scores above 70 indicate very engine-like play in critical moments, and scores above 85 show near-perfect engine matching that is extremely rare for human players.

Question 5

Can I detect if someone used a chess engine during an online game?

Accepted Answer

You can identify games where a player performed suspiciously close to engine-level play. The analyzer checks engine move agreement, accuracy consistency, performance under pressure, and longest streaks of perfect play. A high risk score does not prove cheating - exceptional players can score high in individual games - but it flags games that deserve closer scrutiny.

Question 6

What is centipawn loss and how does it help detect cheating in chess?

Accepted Answer

Centipawn loss measures how much worse a played move was compared to the engine best move, in hundredths of a pawn. An average centipawn loss under 15 across a full game is extremely engine-like. Humans typically average 40 to 100 depending on rating. The analyzer also looks at centipawn loss consistency - bots tend to have very uniform accuracy while humans naturally fluctuate between brilliant moves and occasional mistakes.

Question 7

Does this chess fair-play tool work with Lichess games?

Accepted Answer

Yes. The analyzer accepts standard PGN notation from any chess platform - chess.com, Lichess, chess24, or any app that exports PGN. If the PGN includes clock data, the analyzer also checks whether the player spent more time thinking in critical positions, which is a natural human pattern that bots often lack.

Question 8

How accurate is online chess cheating detection?

Accepted Answer

Single-game detection is inherently probabilistic - it can identify suspicious patterns but not prove intent. A high risk score means the play closely matched engine recommendations in positions where humans typically struggle. The analyzer is transparent about its methodology: it shows every metric, every suspicious move, and lets you review positions on the board yourself. It is a forensic tool for investigation, not an automatic verdict.

Question 9

Can I review suspicious moves on a chess board after the analysis?

Accepted Answer

Yes. After the analysis completes, open the board review panel to step through the game move by move. Each move is shown with colored arrows - green for normal play, blue for notable accuracy, grey for suspicious moves, and red for highly suspicious moves. Blunders by the opponent show the engine best move as a dashed arrow. You can jump to any of the top suspicious moves or blunders with one click.

Question 10

What chess cheating patterns does the bot detector look for?

Accepted Answer

The detector looks for several engine-like signals: unusually low centipawn loss, high rate of matching the engine first choice, long streaks of perfect engine moves, uniform accuracy without natural fluctuation, strong performance specifically in critical positions where the best move is hard to find, and lack of time-pressure correlation if clock data is available. No single signal proves anything - it is the combination that raises or lowers the risk score.

Spider Chess

Spider Chess

Bot Detector (PGN)