XML Validator

Check XML syntax and read the browser parser's error details without uploading your document.

Up to 200,000 characters. UTF-8 files up to 800,000 bytes. Output limit: 4,000,000 characters. Maximum nesting: 256 elements.

Download report

Your source is processed in your browser and is not uploaded to ToolPixels. This tool does not save your input.

How to use it

  1. Paste XML or open a UTF-8 file. Load the example to try it.
  2. Select Validate XML.
  3. Read the report or correct the parser error and check again.
  4. Copy the result or download xml-validator.txt.

Well-formed does not mean schema-valid

Checks for a single root, matching tags, quoted attributes, and valid XML syntax. It does not validate XSD schemas, DTD rules, or application requirements. Error wording and line information depend on your browser.

DTDs and entity declarations are not supported. External documents are never loaded. Standard XML entities such as & and numeric character references are supported. Downloads use UTF-8; the formatter updates any encoding declaration accordingly.

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