Plychess
Real-time Stockfish 16.1

Free Chess Analysis Lab

Industry-standard engine depth and positional evaluation. No sign-up, no server lag, 100% private.

Current Matchup
WhitevsBlack
8br
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7bp
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2wp
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1awr
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Stockfish 16.1 Analysis
High-performance engine running in your browser.
Engine Status
idle
Live Engine Output
Waiting for engine calculation...
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Take Your Preparation to the Master Level

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Why use Plychess for Analysis?

The most powerful browser-based chess toolkit available in 2026.

WASM Multi-Threading

Our Stockfish 16.1 implementation uses SharedArrayBuffer to harness your full CPU power for up to 8x faster calculation.

PGN & FEN Support

Seamlessly import entire chess games via PGN or set up specific tactical puzzles with FEN strings instantly.

100% Client-Side

Your data stays in your browser. All analysis happens locally, ensuring 100% privacy for your secret opening prep.

Master the Evaluation Bar

The evaluation bar is your window into the mind of Stockfish. A positive score (e.g., +1.5) indicates White has the advantage, while a negative score indicates Black is better.

Use our Interactive Analysis Lab to explore different variations. By understanding why the evaluation changes, you'll develop the positional intuition needed to reach the 2000+ ELO bracket.

Read our Analysis Guide

+2.4 Advantage

Real-time Feedback

Analysis Frequently Asked Questions

How deep can the Stockfish engine analyze?

Depending on your hardware, our WASM Stockfish 16.1 can reach depths of 20 to 24 plies within seconds. For Pro users, you can override depth limits for infinite analysis.

Can I import games from Chess.com or Lichess?

Yes! Simply paste your PGN into the input area. Our engine will automatically parse the moves and prepare the board for deep analysis.

What is MultiPV in chess analysis?

MultiPV allows the engine to show multiple best lines simultaneously. Plychess provides up to 3 lines by default, helping you find creative alternatives to the top engine move.

Is Plychess unblocked at school?

Most likely! Because our engine runs entirely in the browser using WebAssembly and doesn't rely on restricted backend servers, it bypasses many traditional network filters.