About the JSON Syntax Highlighter
Turn plain JSON into colorized, readable code. Copy the highlighted HTML to paste into documentation, blog posts or emails.
Key features
- Colors keys, strings, numbers, booleans and null
- Outputs self-contained HTML with inline styles
- Live preview of the highlighted result
- No external CSS or JavaScript required to display it
- Pretty-prints the JSON automatically
- Copy or download as an .html file
What is JSON syntax highlighting?
Syntax highlighting colors each part of the code according to its role. For JSON that means keys, string values, numbers, booleans and null each get their own color, so the structure is easy to scan. Editors do this automatically, but when you want to publish JSON in a blog post, documentation page or email, you need highlighted HTML.
This tool formats your JSON and wraps every token in a <span> with an inline color, producing a self-contained <pre> block you can paste anywhere.
Color scheme
| Token | Example | Color |
|---|---|---|
| Key | "name": | Rose |
| String | "Ada" | Green |
| Number | 42 | Blue |
| Boolean | true | Purple |
| Null | null | Grey |
Where to use highlighted JSON
- API documentation. Show example requests and responses that are easy to read.
- Technical blog posts. Platforms without built-in code highlighting.
- Emails and newsletters. Inline styles survive most email clients, unlike external stylesheets.
- Slides and reports. Paste into tools that accept HTML or rich text.
- Internal wikis. Confluence, SharePoint or Notion HTML embeds.
How it works
- Your JSON is parsed and pretty-printed with 2-space indentation (invalid JSON shows an error instead).
- The text is HTML-escaped so it's safe to embed.
- Each token is matched and wrapped in a colored
<span>. - Everything is placed in a styled
<pre>block.
Use Preview to see how it will look before copying.
Tips
- Keep examples short. Trim large payloads to the fields that matter. The JSON Cleaner helps remove empty values.
- Dark backgrounds. The default palette is designed for light backgrounds; adjust the
backgroundvalue on the<pre>tag and the token colors for dark themes. - Need plain text instead? Use the JSON Formatter to get indented JSON without markup.
Related tools
To show tabular data as a real HTML table instead of code, use JSON to HTML.
How to use the JSON Syntax Highlighter
- Paste your data into the input box, upload a file, or click Sample to try it out.
- Adjust the options above the editor if you need to (indentation, delimiter, and so on).
- The result appears instantly in the output panel. Any errors are shown with their line and column.
- Click Copy to copy the result, or Download to save it as a file.