Code Snippet Highlighter
Highlight code snippets
What Is This Tool?
The Code Snippet Highlighter applies simple, regex-based syntax highlighting to a pasted code snippet, wrapping keywords, strings, comments, and numbers in styled <span> tags. It gives you both a live preview and the raw HTML output to embed elsewhere.
How to Use
Paste your code into the textarea and choose its language.
Click Highlight to tokenize keywords, strings, comments, and numbers.
Review the colored preview and copy the generated HTML for use elsewhere.
Features
- Supports JavaScript, JSON, CSS, HTML, SQL, and plain text
- Highlights keywords, string literals, comments, and numbers
- Escapes all input first, so no user text can inject real markup
- Live styled preview plus copyable raw HTML output
- Uses theme-aware colors that adapt to light and dark mode
- 100% client-side — nothing leaves your browser
Examples
Input (JavaScript):
function greet(name) { // say hello
return `Hello, ${name}!`;
}
Output: "function" and "return" highlighted as keywords, the comment dimmed, and the template string colored as a string literal.
Common Use Cases
- Embedding a simply-highlighted code sample into a blog post or wiki page
- Quickly previewing how a snippet would look with basic syntax coloring
- Generating lightweight highlighted HTML without loading a full highlighting library
- Reviewing keyword and string usage in a short snippet
Frequently Asked Questions
Is this a full syntax highlighter like Prism or highlight.js?
No. This is a lightweight, regex-based highlighter that recognizes common keywords, strings, comments, and numbers. It won't catch every language nuance the way a full parser-based highlighter would.
Is it safe to paste code that contains HTML tags?
Yes. The entire input is HTML-escaped before any highlighting markup is added, so tags, quotes, and special characters in your code are always rendered as text, never executed as markup.
Which languages are supported?
JavaScript, JSON, CSS, HTML, SQL, and a Plain Text mode that only highlights strings and numbers without a keyword list.
Can I use the output HTML directly in my own page?
Yes, copy the generated HTML and paste it wherever you need it. You'll need to include your own CSS rules for the .tok-keyword, .tok-string, .tok-comment, and .tok-number classes to get the same colors.
Does the highlighter understand nested language contexts (like JS inside HTML)?
No, choose the language that matches the majority of your snippet. Mixed-language snippets will be highlighted using only the single selected language's rules.
Is my code sent anywhere?
No. Highlighting happens entirely in JavaScript in your browser. Nothing is uploaded or logged.