Tampermonkey Chess - Script

If you want to learn chess, use:

Here lies the critical section. Using a Tampermonkey chess script is not inherently bad—but how and when you use it determines its morality and legality.

Simple panel (HTML div) with buttons to enable/disable features.

Tampermonkey scripts run in your browser to modify web pages. For chess:

Legitimate uses (learning/tools):

Cheating (bannable/unethical):

⚠️ Most chess sites (Chess.com, Lichess, etc.) detect engine assistance and will ban you. Keep scripts informational only — no automatic or hidden analysis.

As of 2026, the chess platform arms race has intensified:

The days of simple Tampermonkey auto-players succeeding for more than a handful of games are over. Platform engineers are former competitive programmers who understand script injection patterns intimately. tampermonkey chess script

That said, script developers continue to evolve—adding randomness, human-like error rates, and mouse movement simulation. It’s a cat-and-mouse game that ultimately harms the entire chess community.

Let’s write a script that draws a red ring around the king on Chess.com.

// ==UserScript==
// @name         Chess King Highlighter
// @namespace    http://tampermonkey.net/
// @version      1.0
// @description  Highlights the king in red on Chess.com
// @author       You
// @match        https://www.chess.com/game/*
// @grant        none
// ==/UserScript==
(function() 
'use strict';
function highlightKing() 
    // Find all pieces on the board (Chess.com uses 'piece' class)
    const pieces = document.querySelectorAll('.piece');
    pieces.forEach(piece => 
        // Check if piece is a king (typically 'k' in class or alt text)
        if (piece.classList.contains('wk') );
// Run every second because the DOM changes after moves
setInterval(highlightKing, 1000);

)();

What this script does: Every second, it scans the Chess.com game page for pieces with the wk (white king) or bk (black king) class and adds a red glow.

Is this cheating? No. It does not evaluate the position; it only visually highlights a piece you can already see.

To expand this script, you could: