Best Free Online Developer Tools to Use in 2026
A practical, opinionated list of the best free online developer tools worth using in 2026, organized by category so you can find what you need fast.
Aug 08, 2026
XML Formatter & Beautifier
Format, beautify, and validate your XML data instantly. Supports attributes, CDATA, namespaces, and more.
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What is XML?
XML (eXtensible Markup Language) is a markup language designed for storing and transporting data. It is both human-readable and machine-readable, making it a popular choice for data exchange between different systems, configuration files, and document formats.
XML uses custom tags to define elements, attributes for metadata, and a tree-like structure to represent data hierarchies. Unlike HTML, XML tags are not predefined — you create your own tags to describe your data.
How to Use
- Paste your XML — Copy and paste any XML data into the top textarea. You can also type directly or use the Example link to load sample XML.
- Choose options — Select indentation style (2 spaces, 4 spaces, or Tab). Toggle attribute sorting and XML declaration inclusion.
- Format or Minify — Click Format XML to beautify with proper indentation, or Minify to compress into a compact form.
- Validate — Click Validate to check for well-formedness errors.
- Copy or download — Use the copy button on the output area or click Download .xml to save the result.
Frequently Asked Questions
What is the difference between XML and HTML?
HTML is a presentation language designed for displaying content in web browsers. XML is a data-format language designed for storing and transporting data. HTML has predefined tags, while XML lets you create your own tags.
Is my XML data stored on a server?
No. All processing happens entirely in your browser using JavaScript. Your XML data never leaves your device.
What does XML validation check for?
Validation checks for well-formedness: matching opening/closing tags, proper attribute quoting, correct nesting, and valid character encoding. Note: this tool validates structure, not against a DTD or XSD schema.
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Last updated: 17 Aug 2026
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