W3C Markup Validation Service down?
A tool for validating HTML, XHTML, and other markup documents.
Recent User Report Trends for W3C Markup Validation Service
Aggregated reports in the last 48 hours.
What is W3C Markup Validation Service's current status?
All systems are operational
No active incidents reported.
User Reports for W3C Markup Validation Service
Recent issues reported by users from around the world (last 30 days).
Performance Insights
Performance
98/ 100
Accessibility
94/ 100
Best Practices
71/ 100
SEO
100/ 100
Page Load Time
0.77s
Page Size
0.05MB
Requests
9
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About W3C Markup Validation Service & Technical Insights
The website targets web professionals and anyone involved in web content creation who aims to ensure their web documents conform to W3C standards, improving technical quality, cross-browser compatibility, and accessibility. [4, 8, 29, 33, 35]
Technologies Used
Website Details & Offering
Primary Call to Action
Check (or Validate)
Secondary Calls to Action
Validate by File UploadValidate by Direct InputMore Options (for validation)View Source (after validation)Show an outline of this document (after validation)HelpFeedback
Advertisements Present?
None
Allows User Accounts?
No
Headquarters Country
Global
Language
English
Primary Category
Technology and Software
Revenue Source
None (Informational)
Pricing Summary
N/A (Free public service) [8, 32]
Value Proposition
The W3C Markup Validation Service provides a free, web-based tool to check the markup (HTML, XHTML, etc.) validity of web documents against W3C standards, helping to ensure technical quality, cross-browser compatibility, and accessibility. [4, 8, 9, 33, 34, 35]
Content & Features
Tone & Style
FormalTechnicalAuthoritativeInformativeFunctional
Content Freshness Clues
No explicit dates on the main pageDocumentation often includes 'Last Updated' dates on specific help pages (e.g., help.html linked from the site suggests looking for FAQ updates)Underlying tools are regularly updated (e.g., mentions of HTML5 engine in 2008, HTTPS support updates mentioned in Stack Overflow discussions [35, 45])
Highlighted Features
Markup validation (HTML, XHTML, SMIL, MathML, SVG, SGML, XML DTD) [8, 34, 35]Validation by URI, File Upload, or Direct Input [34]Detailed error reporting and suggestions [4, 9, 10]Cross-browser compatibility checking (indirectly by adhering to standards) [8, 9]Accessibility enhancement (indirectly by adhering to standards) [4, 9, 29]SEO benefits (indirectly by improving site performance and user experience) [4, 9, 30, 33]Options for showing source input and document outline [10, 25]
Mentioned Integrations
API for programmatic validation (GET and POST interfaces, JSON/XML output options) [25, 46]Mentioned in context of various external tools and services that integrate or refer to it (e.g., Drupal module, Screpy, Rocket Validator) [2, 15, 36, 43]
Target Audience Insights
Target Country
Global
Target Category Focus
Technology and Software
Audience Expertise Level
Intermediate to Expert
Job Type
Web Developers, Web Designers, Webmasters, QA Engineers, Content Creators
Geographic Focus
All
Brand Preference
Open Standards, W3C
Education
Technical, Intermediate to Advanced
Target Age Range
All (Adults primarily)
Device Type
Desktop (for development)
Interests
Web Standards, Web Development, Website Quality, Accessibility, SEO (indirectly)
Tech Skills
High
Trust & Support Signals
Support Channels Mentioned
Mailing lists (e.g., public-validator@w3.org) [27]Usenet newsgroup (comp.infosystems.www.authoring.html) [27]IRC channel (#validator on freenode) [27]Bug tracking system (Bugzilla) [27]Email (sysreq@w3.org for technical problems, site-comments@w3.org for website feedback) [28]
Trust Signals Present
Official W3C branding and domain (w3.org)Clear statement of purpose (validates against W3C standards) [34]Comprehensive documentation and help [10, 27]Open-source nature of the underlying tools (implied, mentioned in alternatives context) [2]Long-standing reputation as a global web standards body [33]
Company Info Sections
About W3C (implied by the domain and purpose)Mission (W3C's mission to lead the web to its full potential is widely known and linked to validation) [30, 33]History (of the validator service mentioned in Wikipedia and documentation) [35]
Related Services & Domains
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Additional Domain & Security Details
- Domain Name
- validator.w3.org
- Last Checked (Registry)
- June 12, 2025 at 06:34:25 AM UTC