Code Syntax Highlighter

Paste code and get beautiful syntax highlighting for 20+ languages with multiple themes

A code syntax highlighter adds color-coded styling to source code so it is easier to read, share, and embed in blogs or documentation. Powered by Prism.js, this tool highlights over 20 programming languages with professional color themes — no editor installation required.

// Highlighted code will appear here after you click Highlight

How to Use the Code Syntax Highlighter

Syntax highlighting makes source code dramatically easier to read by coloring keywords, strings, comments, and operators differently. This code syntax highlighter uses Prism.js — the industry-standard highlighting library used by MDN, Stripe, and thousands of documentation sites — to produce clean, accessible highlighted output directly in your browser.

Step 1: Select a Language

Choose the programming language from the Language dropdown. Over 20 languages are available including JavaScript, Python, HTML, CSS, Java, Go, Rust, SQL, Bash, and more. The correct grammar file is loaded automatically via Prism.js's autoloader.

Step 2: Choose a Theme

Pick a color theme that suits your content. Tomorrow Night and Okaidia are dark themes with high contrast — great for code in documentation. Solarized Light and VS are light themes suitable for printed docs or light-mode blogs.

Step 3: Paste Your Code and Highlight

Paste your code into the input area and click Highlight. The output panel below updates with beautifully colored code. Enable Line Numbers to add a numbered gutter — useful when referencing specific lines. Enable Word Wrap for long lines that would otherwise require horizontal scrolling.

Step 4: Copy or Embed

Use Copy HTML to copy the full syntax-highlighted HTML markup for embedding in a blog post or CMS. Use Copy Plain to copy just the source code text without any markup. All highlighting runs locally in your browser — your code is never uploaded to any server.

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FAQ

Is this syntax highlighter free?

Yes, completely free. No account required, no limits, no watermarks.

What programming languages are supported?

Over 20 languages are supported via Prism.js: JavaScript, TypeScript, Python, HTML, CSS, Java, C, C++, Go, Rust, Ruby, PHP, SQL, Bash, JSON, YAML, Markdown, XML, Swift, Kotlin, R, and more. Prism.js auto-detects the required grammar.

What themes are available?

Five themes are available: Tomorrow Night (dark), Okaidia (dark), Solarized Light, One Dark, and VS (VS Code style). Switch themes instantly with the dropdown.

Can I copy the highlighted HTML to use in a blog or presentation?

Yes. After highlighting, click Copy HTML to copy the full highlighted HTML markup including CSS classes. You can paste this into any blog post, CMS, or presentation that accepts raw HTML.

Can I enable line numbers?

Yes. Toggle the Line Numbers switch and your code will display with line numbers in the gutter, powered by Prism.js's line-numbers plugin.

Does word wrap work in the highlighted output?

Yes. Toggle Word Wrap to control whether long lines wrap in the output or scroll horizontally.

Is my code sent to any server?

No. Syntax highlighting runs entirely in your browser using Prism.js loaded from CDN. Your code is never transmitted to any server and is not stored or logged.

What is Prism.js?

Prism.js is one of the most popular open-source syntax highlighting libraries, used by major documentation sites like MDN and Stripe. It supports over 200 languages with clean, accessible output.