xmllint VS xmlvalid

• Validation
  xmllint can be used to validate XML documents against a DTD, which helps ensure the XML structure adheres to a predefined specification.
• XPath Support
  It offers the ability to evaluate XPath expressions, which allows users to query specific parts of the XML document efficiently.
• Format and Beautify
  xmllint can reformat XML documents to make them more readable, which is especially helpful for debugging and reviewing code.
• Wide Compatibility
  As part of the libxml2 project, xmllint is compatible with various systems and supports a wide range of XML standards, making it versatile for different environments.
• Command-line Usage
  Being a command-line tool, xmllint can be easily scripted and used in automated processes or integrated into development pipelines.

Possible disadvantages

• Complexity for Large Documents
  Handling very large XML documents can be computationally intensive, and xmllint might struggle with performance or memory usage in such cases.
• Limited Error Descriptions
  Error messages produced by xmllint may not always be detailed, which can make debugging difficult for users without extensive XML knowledge.
• No XML Schema Validation
  While xmllint supports DTD validation, it does not offer native support for validating XML Schema, which limits its applicability for XML documents based on XML Schema definitions.
• Learning Curve
  Users unfamiliar with command-line tools may find xmllint challenging to use initially due to its text-based interface and wide range of options.
• Limited Interactive Use
  Unlike some graphical XML tools, xmllint does not provide an interactive user interface, which may not appeal to users preferring visual tools for working with XML.

• Schema languages
  XSD 1.0, DTD, RelaxNG (XML and compact)
• Business rules
  7,700+ Schematron rules (EN 16931, Peppol BIS and PINT, XRechnung, Factur-X, national CIUS) plus your own .sch
• Schema catalog
  177 official schemas with all their include files
• Country guides
  E-invoicing in 24 countries, the profile picked from the invoice automatically
• Max File Size
  50 MB without an account, 1 GB with a free account (5 GB tested)
• Batch validation
  A folder or .zip of up to 1,000 documents
• Privacy
  Validated in the browser, nothing uploaded
• Input methods
  Upload, paste, URL, or a folder or .zip of up to 1,000 documents
• PDF invoices
  Factur-X, ZUGFeRD and ISDOC, with PDF/A (veraPDF) and PDF text checks
• Error details
  Line and column, explanations for libxml2, Java (Xerces) and .NET messages
• E-invoice Detection
  Profile picked automatically from the document
• API
  REST (OpenAPI 3.1), SOAP, MCP server, SDKs for PHP, Laravel, Symfony, Python and JavaScript
• CLI
  CLI (npm @xmlvalid/cli), GitHub Action, GitLab CI, pre-commit
• URL monitors
  Alerts by email or webhook when a feed starts failing
• Reports
  PDF, HTML, JSON export, share links
• Dark Mode
• Integrations
  n8n, Apify, Postman
• Monitoring
  URL monitors with email and webhook alerts
• Free Tools
  XML formatter, XPath tester, XSLT transformer, XML diff, XML to JSON / CSV, XSD generator, XSD to XML, e-invoice viewer

• Generate RSS feeds with grep(1), sed(1), and Awk(1)

  I strongly recommend adding a schema validator to anything that generates XML. ATOM¹ has a nice schema available² that you can use at the end to check the whole thing (I use xmllint³, since it is in a lot of package repositories).... - Source: Hacker News / over 5 years ago

• looking for html beautifier

  There is also pup. Or if you want to go with a lot more options with xmllint. Of if you want just to render the html in your terminal. Source: over 5 years ago

Tracking xmlvalid since Oct 2026.