XML Formatter & Validator

PRACTICAL GUIDE · UPDATED OCTOBER 17, 2026

Format XML while checking text, tags, and whitespace

The XML tool formats, minifies, and checks whether a pasted document can be parsed. Use it for a small configuration or message you need to read, while keeping a separate original. It is not an XSD validator, a DTD validation service, or an XML signature and canonicalization tool.

Try a simple fictional record

<record id="demo-7"><name>Example</name><active>true</active></record>

Select Format and check that the attribute, element names, and text remain recognizable. Minify produces a compact representation; Validate checks parsing. To copy a generated result, use Format or Minify first. The Copy button uses the output, rather than the input.

Explore the document

Choose 2, 3, 4 spaces or tabs. Tree shows the input structure, element names, attributes, comments and text; expand or collapse branches as needed. Text shows the generated result. Find searches input or output. Auto-format is optional; Ctrl/Cmd + Enter formats immediately. Expand workspace gives you more room and Escape exits. Line numbers appear with wrapping off.

XML → JSON produces an ordered document model with element names, namespaces, an attributes list and ordered children. Text, CDATA, comments and processing instructions have explicit types. This avoids silently merging repeated elements or rearranging mixed content. It is a conversion representation, not an application-specific JSON schema. Download uses .json for converted output and .xml for XML; Use as input is available for XML output.

Browser processing supports UTF-8 files up to 1 MB, 128 nesting levels and 20,000 nodes. Tree display is capped at 5,000 nodes; use Text for larger results. DOCTYPE and entity declarations are rejected. Browser output downloads as UTF-8. No automatic saving or external URL loading is performed.

Resolve common parser errors

XML element names are case-sensitive. A start tag named record cannot be closed with Record. Make sure nested tags close in the correct order, attributes are quoted, and the document has the required root structure. An ampersand in ordinary text must be represented correctly, such as & for a literal ampersand. Do not replace every ampersand indiscriminately if existing entities are already valid.

Be careful with mixed text

When words and child elements share a parent, whitespace can be part of the content. The browser formatter and minifier preserve subtrees containing mixed text, CDATA or inherited xml:space="preserve". Whitespace-only leaf values are retained. Layout whitespace in element-only content may change; parsing can normalize entity spelling and attribute quotes. For prose, templates, or other mixed-content documents, inspect the resulting text and use a purpose-built XML workflow if whitespace preservation is essential. A compact document is not automatically equivalent for every consumer.

Validate the receiving contract separately

A parsed XML document can still contain the wrong attribute names, missing fields, or unexpected namespaces for your integration. Check those against the system's schema or documentation. Browser processing is used when the client path is available; server fallback requests can send the pasted content to the host. Use fictional values for debugging and preserve signed or confidential originals in a controlled environment.

See DOMParser documentation for browser parsing behavior.

Use Try a sample, Open file (UTF-8 text up to 1 MB), Clear, Copy or Download output. Review mixed-content XML and whitespace-sensitive values after formatting or minifying; use Validate when you only need a syntax check.