Is my input uploaded?

No. fast-xml-parser (MIT) runs as JavaScript entirely in your browser. Sensitive payloads (internal API responses, config files) stay on your device.

How are attributes preserved?

On the JSON side, attributes appear as keys prefixed with `@_`. For example ` Hello ` becomes `{ "title": { "#text": "Hello", "@_lang": "en" } }`. Elements with both text and attributes use `#text` for the body.

How do I emit attributes in JSON → XML?

Start the key with `@_` to make it an attribute, and use `#text` for the body text. For instance `{ "book": { "#text": "body", "@_id": "b1" } }` becomes ` body `.

Are number and boolean types preserved?

On XML → JSON, contents that look like numbers / booleans (` 1925 `) are automatically inferred to number / boolean. To keep them as strings, quote the digits explicitly or post-process the JSON.

Are the XML declaration and DOCTYPE handled?

The XML declaration (` `) is preserved as a `?xml` key on the JSON side. DOCTYPE is dropped. On JSON → XML, including a `?xml` key prepends the declaration to the output.

Back to Developer

XML ↔ JSON Converter

Convert between XML and JSON. Attributes are preserved with `@_` prefix, indent (2 / 4 / tab) selectable. Runs entirely in your browser via fast-xml-parser (MIT) — no uploads.

developerconversionJSON

How to use

Paste XML, pick "XML → JSON", and the loaded fast-xml-parser (MIT) emits a JSON string. The reverse direction (JSON → XML) emits pretty-printed XML the same way. Attributes are kept with an `@_` prefix and text nodes go into a `#text` key. Indent (2 / 4 / tab) is selectable. Everything runs in your browser — your data is never uploaded.

FAQ

Is my input uploaded?: No. fast-xml-parser (MIT) runs as JavaScript entirely in your browser. Sensitive payloads (internal API responses, config files) stay on your device.
How are attributes preserved?: On the JSON side, attributes appear as keys prefixed with `@_`. For example `<title lang="en">Hello</title>` becomes `{ "title": { "#text": "Hello", "@_lang": "en" } }`. Elements with both text and attributes use `#text` for the body.
How do I emit attributes in JSON → XML?: Start the key with `@_` to make it an attribute, and use `#text` for the body text. For instance `{ "book": { "#text": "body", "@_id": "b1" } }` becomes `<book id="b1">body</book>`.
Are number and boolean types preserved?: On XML → JSON, contents that look like numbers / booleans (`<year>1925</year>`) are automatically inferred to number / boolean. To keep them as strings, quote the digits explicitly or post-process the JSON.
Are the XML declaration and DOCTYPE handled?: The XML declaration (`<?xml version="1.0" encoding="UTF-8"?>`) is preserved as a `?xml` key on the JSON side. DOCTYPE is dropped. On JSON → XML, including a `?xml` key prepends the declaration to the output.

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