How Validador de Sitemap XML Works
A Sitemap Validator is a critical SEO utility used to verify that an XML Sitemap file adheres to the rigorous protocol defined by search engines. This tool is essential for Webmasters, SEO Specialists, and Content Managers ensuring Google, Bing, and other search engines can properly index their site structure.
The validation engine handles the XML schema check through a strict compliance pipeline:
- XML Syntax Verification: The tool first checks if the file is "Well-Formed" XML (proper closing tags, correct encoding headers, and valid nesting).
- Schema Validation (XSD): It compares your file against the official sitemaps.org schema definition. This ensures you are using the correct
<urlset>and<url>hierarchy. - Tag Constraint Checking:
<loc>: Must be a valid, absolute URL (starting withhttp://orhttps://).<lastmod>: Checks for valid W3C Datetime format (YYYY-MM-DD).<changefreq>: Verifies values are within the allowed set (always, hourly, daily, weekly, monthly, yearly, never).<priority>: Ensures the value is a float between 0.0 and 1.0.
- Limit Detection: The tool flags if your sitemap exceeds the 50MB file size limit or the 50,000 URL count limit imposed by Google.
- Reactive Real-time Feedback: Paste your XML code directly to see instant error highlighting without needing to save and upload a file.
The Standard: Sitemaps.org Protocol
Before 2005, site crawling was chaotic.
- Google Sitemaps (2005): Google introduced the Sitemap 0.84 protocol to allow webmasters to feed URLs directly to the crawler.
- The Sitemaps.org Alliance (2006): In a rare moment of unity, Google, Yahoo!, and Microsoft joined forces to support a single, common protocol (Sitemap 0.90), which remains the standard today.
- Video & Image Extensions: Later updates added specialized tags to help index rich media content, which this validator also recognizes.
Common Sitemap Errors
| Error Type | Description | Fix |
|---|---|---|
| Invalid Date | <lastmod>12/31/2023</lastmod> |
Use ISO 8601: 2023-12-31 |
| Relative URL | <loc>/about-us</loc> |
Use Absolute: https://site.com/about |
| Invalid Priority | <priority>1.5</priority> |
Must be between 0.0 and 1.0 |
| Namespace Error | Missing xmlns attribute |
Add correct schema to <urlset> |
Technical Depth: Why "Well-Formed" Isn't Enough
A sitemap can be valid XML but still fail Google Console validation. Our tool checks for Logic Errors that generic XML parsers miss. For example, declaring a <loc> that points to a non-existent domain, or using a <changefreq> of "sometimes" (which is invalid). We also check for Entity Encoding issues (e.g., using & instead of & in URLs), which is the #1 cause of crawling failures.