1. What is Chess Accuracy?

Chess accuracy measures how closely a player's moves match what a chess engine would recommend. It's expressed as a percentage, with higher values indicating better play.

2. How Does the Calculator Work?

The calculator uses the accuracy formula:

Where:

• Engine Eval Difference — The evaluation difference between your move and engine's recommended move (in centipawns)
• Max Possible Difference — The worst possible evaluation difference for that position

Explanation: The formula compares your move's evaluation to both the best move and worst possible move in the position.

3. Importance of Accuracy Calculation

Details: Accuracy percentage helps players understand how well they're playing objectively, track improvement over time, and identify weaknesses in their game.

4. Using the Calculator

Tips: Enter the engine evaluation difference and maximum possible difference (both in centipawns) from your chess analysis software. Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What's a good accuracy percentage?
A: For humans, 80%+ is excellent, 70-80% is good, 50-70% is average, below 50% needs improvement. Grandmasters often achieve 90%+.

Q2: How do I get these values from chess software?
A: Most chess programs (like Lichess, Chess.com, Stockfish) show evaluation differences when analyzing games.

Q3: Does higher accuracy always mean better play?
A: Generally yes, but accuracy can vary by position type. Complex tactical positions typically have lower accuracy than quiet positions.

Q4: Why use centipawns instead of pawn units?
A: Centipawns (1/100th of a pawn) allow for more precise measurement of small evaluation differences.

Q5: Can I calculate accuracy for an entire game?
A: Yes, you would average the accuracy across all moves, though this calculator handles single-position accuracy.