Xmlvalidation
xmlvalidation.com
Validate XML files
Use our tool to quickly validate your XML files against standard syntax or custom schemas.
An example
A web-based XML validator. Can be used for free. Validates XML files, prompts the user for referenced files (e. g., XSD), shows good error messages.
Documentation
A web-based XML validator. Can be used for free. Validates XML files, prompts the user for referenced files (e. g., XSD), shows good error messages.
Videos
11:33
Probatio integra Lex (XML Validator) Overview - YouTube
14:47
7 XML Validation Tools - YouTube
10:51
How to use online XML/HTML validation tools - YouTube
04:57
How to validate xml online - YouTube
04:39
Validate XML syntax and schema - YouTube
12:06
Validate XML Documents Using DTD and Visual Studio - YouTube
Does anyone know how to validate XML in VScode?
No, but the W3C Validation Service validates XML against a DTD, I think. I don't know if it can validate against a schema.
Edit: a quick search indicates that there are several NPM packages which will do XML validation. You could write an NPM script that watches for changes to the XML and runs validation, and run that script through the NPM scripts explorer in VSCode.
More on reddit.comAre there any free XML editors that you guys extensive use?
Not purely XML editors, but feature-rich text editors I love include: Sublime Text 2 Notepad++ Programmer's Notepad More on reddit.com
XML Validation with Powershell
Very nice, very helpful. I would point out the use add-member for $script:validationresults is deprecated (maybe only for aesthetics?), as PS v3 allows something like this:
$script:validationresults = New-Object PSObject -property @{
XMLFile = $xmlFile;
ValidationComplete = $true;
isValid = $true;
Errors = @();
} More on reddit.com Perl 5 XML Validation with DTD and XSD
Talking about XML validation: both DTD and XSD are horrible. DTD is very simplistic and forces a specific order of elements, and XSD is bloat and impossible to write. What happened to RelaxNG? That was my favourite. You can write in easily readable compact form, transform it to XML which can be used for validation in XML::LibXML. EDIT: just a clarification: as Gabor Szabo's newsletter summarized your article with "not every liked it (sic)" with a link to this comment section. That's not the case! I liked your article! It's just that I'm not particularly fond of XML. When I ask people why they use it, I often get: "You can validate it!" My next question of course is what they use for validation, on which I usually get a blank stare, which I interpret as: "we could if we wished to so", so the question of which they use - DTD or XSD - answered itself. More on reddit.com
W3Schools
w3schools.com βΊ xml βΊ xml_validator.asp
XML Validator
Use our XML validator to syntax-check your XML.
FreeFormatter
freeformatter.com βΊ xml-validator-xsd.html
Free Online XML Validator Against XSD Schema - FreeFormatter.com
This free online XML validator lets you validate your XML files against an XSD (XML Schema)
Truugo
truugo.com βΊ xml_validator
XML Validator - Validate XML Online
Use the XML validator to perform syntax check and to validate XML using schema validation (XSD + DTD). The XML editor helps to fix simple bugs and to beautify/minify your XML output.
W3C
validator.w3.org
The W3C Markup Validation Service
W3C's easy-to-use markup validation service, based on SGML and XML parsers.
ReqBin
reqbin.com βΊ xml-validator
Online XML Validator
August 7, 2023 - Validate XML data strings for XML errors with best-in-class XML linter and XML validator. View XML validation results in an advanced XML editor with built-in syntax highlighting and per-line error indication.
CoreFiling
corefiling.com βΊ home βΊ open source tools βΊ online xml schema validator
Free Online XML Schema Validator from CoreFiling
June 20, 2025 - The original and best, world's most popular online XML schema validator. Test your XML against provided or external schema.
BeautifyTools
beautifytools.com βΊ xml-validator.php
Online XML Validator - BeautifyTools.com
Online XML Validator validates XML markup and makes a list of errors and warnings from your XML code that can be fixed.
XmlLint
xmllint.com βΊ home
XmlLint - Awesome XML Formatting & Beautification
September 12, 2021 - Meet XmlLint β a powerful, yet very modern client-only XML formatting and validation tool that can format, validate, or beautify any document or XML snippet (and do it all in a matter of a few seconds)!
Utilities and Tools
utilities-online.info βΊ xsdvalidation
W3C XML Schema (XSD) Validation online
Validate XML data against an XSD (XML Schema Definition) to ensure it follows the correct structure and rules.
Easycodeforall
easycodeforall.com βΊ XMLValidation.jsp
Online Tool To Validate XML against a XSD (XML Schema). online schema validator - www.easycodeforall.com
Online Utility For XML Validation. online schema validator against xsd
Wtools
wtools.io βΊ validate-xml-online
Validate XML, Online XML Validator | WTOOLS
Validate XML - online web based tool who allows you validate and format XML