JSON Syntax Highlighting
Paste JSON to validate, pretty-print, and turn it into syntax-highlighted HTML. Choose a light or dark theme, toggle line numbers, and copy the highlighted snippet for docs, blogs, or internal tools.
Last updated: May 28, 2026
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Buy me a coffeeWhat is JSON Syntax Highlighting?
JSON syntax highlighting adds color to keys, strings, numbers, booleans, null values, and punctuation so JSON is easier to scan. It is useful for documentation, tutorials, changelogs, API examples, and debugging notes where plain JSON would be hard to read.
This tool first parses JSON strictly, then formats it with consistent indentation and emits escaped HTML. Because values are escaped before highlighting, pasted JSON is treated as source text rather than executable markup.
How to Use JSON Syntax Highlighting
Paste valid JSON into the input panel.
Choose dark or light highlighting.
Pick the indentation size and whether to show line numbers.
Preview the highlighted result.
Copy the generated HTML, copy formatted JSON, or download an HTML file.
Common Use Cases
- Create highlighted JSON examples for API documentation.
- Format configuration snippets for internal runbooks or wikis.
- Prepare readable JSON samples for blog posts and tutorials.
- Review JSON structure with line numbers during debugging.
- Generate lightweight highlighted HTML without a client-side library.
Example Input and Output
A JSON API status object is formatted and wrapped in highlighted HTML.
{ "healthy": true, "latencyMs": 84.7, "burst": null }<pre><code><span style="color:#9cdcfe">"healthy"</span>: <span style="color:#569cd6">true</span></code></pre>Privacy
JSON input is parsed and highlighted in the browser. It is not uploaded.
Embedding output
The copied HTML uses inline styles so it can be pasted into many CMS editors and documentation systems without requiring an external stylesheet.