Highlight.js Syntax Highlighting

Syntax Highlighting for the Web

Highlight.js is a syntax highlighter written in JavaScript. It works in the browser as well as on the server with Node.js. The highlight function detects the language automatically.


function greet(name) {
  // This is a syntax highlighted code block
  if (name) {
    console.log(`Hello, ${name}!`);
  } else {
    console.log("Hello, stranger!");
  }
}

greet("World");

.language-javascript class applied automatically

⚡

Lightweight

Core is small (~9.5KB) and fast

🌐

Multi-Language

Supports 180+ languages

🧠

Autodetect

Automatic language detection

How It Works

1. Include CSS


<link rel="stylesheet" href="/highlight.js.min.css">

2. Apply Classes


<pre><code class="language-javascript">...</code></pre>

CSS Code


body {
  background-color: #f0f0f0;
  color: #333;
  transition: background 0.3s, color 0.3s;
}

.dark {
  background-color: #121212;
  color: #f0f0f0;
}

Python Code


def fibonacci(n):
    if n <= 1:
        return n
    else:
        return fibonacci(n-1) + fibonacci(n-2)

# Print the first 10 Fibonacci numbers
for i in range(10):
    print(fibonacci(i))