HTML to JSON Converter

Use HTML to JSON Converter, review the result, and keep the original until the output is checked.

Input HTML
HTML Input
Converted JSON
JSON Output
Click "Convert to JSON" to see converted JSON here...
Structure Preview
Converted structure will appear here...
100% browser-side processing — your data is never uploaded to any server. · Per-tool input limit: 1 MB
100% browser-based No upload to server Free to use

Frequently Asked Questions About HTML to JSON Converter

Is this a W3C validator?

No. It tidies and reports structural problems locally. The W3C checker applies the full specification and returns numbered conformance errors.

Will formatting break my page?

Content stays the same, but whitespace inside <pre>, <textarea> and inline element gaps can shift layout. Preview before shipping to a template that is sensitive to spacing.

Can it fix JSON with trailing commas or comments?

Yes. The repair step removes trailing commas, comments and a byte-order mark, turns single-quoted strings into double-quoted ones and quotes bare member names, then re-reads the document. Values it cannot infer, such as a Python True or a missing closing brace, still need a manual edit.

Why do large numbers change when I format JSON?

JavaScript numbers are IEEE-754 doubles, so most parsers rewrite an integer above 2^53 and lose its tail digits. This page keeps those long literals exactly as you typed them, but a parser elsewhere in your stack will not, so keep such ids as strings in the source document.

What is JSON?

JSON (JavaScript Object Notation) is a lightweight data-interchange format. It uses objects {}, arrays [], strings, numbers, booleans, and null.

Why format JSON?

API responses and config files are often minified. The HTML to JSON Converter expands them with indentation so you can spot nested keys, validate structure, and debug faster.