Sitemap Validator

Validate XML sitemaps against the sitemaps.org schema. Check URL limits, lastmod freshness, sitemap index recursion, .xml.gz files, image/video extensions and robots.txt. Free, private and no sign-up.

What is a free sitemap validator online?

A free sitemap validator online is a tool that checks your XML sitemap file for structural errors, schema violations, URL limits and SEO best-practice issues that could prevent search engines like Google and Bing from crawling and indexing your site. Sitemaps are the roadmap search engines use to discover your URLs — a broken sitemap can waste crawl budget, delay indexing and hide important pages from search results.

This sitemap validator online runs entirely in your browser. It does not upload your sitemap to any server. It parses the XML against the official sitemaps.org schema, validates every URL, checks lastmod freshness, detects image/video/news/mobile extensions, verifies sitemap index recursion, and cross-references robots.txt for blocked URLs. Everything happens locally — no upload, no server, no storage, no tracking.

Why validate your XML sitemap?

Search engines rely on XML sitemaps to discover new and updated pages. If a sitemap contains errors such as malformed tags, incorrect nesting or invalid characters, crawlers may discard the file entirely. This leads to:

• Delayed indexing. New products or articles may not appear in search results for days or weeks.
• Wasted crawl budget. Engines may spend time hitting broken XML files instead of your actual content.
• Index bloat or gaps. If a sitemap index points to broken child sitemaps, large sections of your site may be ignored.

Validating your sitemap before submitting it ensures you provide a clean, technically sound directory to every search engine that visits your domain.

How to use this free sitemap validator online

1. Choose an input method: Fetch from URL, Paste XML or Upload file.
2. For URL mode, enter your sitemap URL (or just a domain). The tool will check robots.txt for a Sitemap: directive and fall back to /sitemap.xml.
3. For file mode, upload a .xml or .xml.gz file. It is decompressed in your browser if gzipped.
4. Click Validate sitemap. The tool parses the XML, runs all checks and reports results.
5. Review the summary, then filter issues by severity (errors, warnings, info).
6. Use Copy report or Download report to save the results.

What this sitemap validator checks

• XML well-formedness. Detects malformed tags, unclosed elements and encoding problems.
• Namespace declaration. Verifies the xmlns="http://www.sitemaps.org/schemas/sitemap/0.9" namespace on <urlset> and <sitemapindex>.
• Root element. Must be <urlset> or <sitemapindex>.
• URL count limit. Flags sitemaps exceeding 50,000 URLs.
• File size limit. Flags sitemaps exceeding 50 MB uncompressed.
• URL length. Flags URLs exceeding 2,048 characters.
• URL format. Requires absolute URLs (with protocol). Detects relative paths.
• Protocol consistency. Flags mixed HTTP and HTTPS within a single sitemap.
• lastmod format. Must be W3C datetime (ISO 8601). Flags invalid dates.
• lastmod freshness. Flags URLs with lastmod older than 6 months.
• changefreq values. Must be one of: always, hourly, daily, weekly, monthly, yearly, never.
• priority values. Must be between 0.0 and 1.0.
• Duplicate URLs. Detects duplicate <loc> entries.
• Whitespace before XML declaration. Detects invisible characters that break XML parsing in WordPress sites.
• Empty or missing <loc>. Flags entries with no URL.
• Image, video, news, mobile extensions. Detects and validates extended namespaces.
• hreflang self-reference. Flags hreflang annotations missing a self-referencing entry.
• Sitemap index recursion. Recursively validates child sitemaps up to a safe depth.
• robots.txt cross-check. Verifies a Sitemap: directive exists and flags URLs blocked by robots.txt.

The 10 most common sitemap errors and how to fix them

1. Whitespace before the XML declaration

A single blank line, space or line break before <?xml causes "XML declaration allowed only at the start of the document". This is extremely common in WordPress sites where a plugin or theme outputs content early. Fix: remove any whitespace before the opening tag in your sitemap generator template.

2. Missing or incorrect sitemaps.org namespace

The <urlset> element must declare xmlns="http://www.sitemaps.org/schemas/sitemap/0.9". An incorrect or missing namespace causes parsing failures in Google and Bing.

3. More than 50,000 URLs in one file

Sitemaps are limited to 50,000 URLs and 50 MB uncompressed per file. Larger sites must split their sitemap into multiple files and reference them from a sitemap index.

4. Missing lastmod dates

Without <lastmod>, search engines cannot tell which pages were recently updated. Add accurate ISO 8601 dates (e.g., 2026-10-01) to every URL entry.

5. Relative URLs instead of absolute URLs

Every <loc> must be a full URL with protocol. /page is not valid; https://example.com/page is.

6. Mixing HTTP and HTTPS

All URLs in a sitemap should use a consistent protocol. If your site uses HTTPS (and it should), ensure every <loc> uses https://.

7. Invalid changefreq values

Only seven values are accepted: always, hourly, daily, weekly, monthly, yearly, never. Any other value is ignored by search engines.

8. Duplicate URLs

Listing the same URL twice wastes crawl budget. Remove duplicates.

9. Missing sitemap reference in robots.txt

Add a Sitemap: https://example.com/sitemap.xml line to your robots.txt so search engine crawlers can automatically discover your sitemap.

10. Blocked URLs included in the sitemap

Listing a URL in both the sitemap and a Disallow directive in robots.txt tells search engines to index it and not to index it simultaneously — a contradiction that may cause the sitemap to be ignored entirely.

Sitemap index files explained

A sitemap index is a parent sitemap that references multiple child sitemaps. It is used when a site has more than 50,000 URLs. Each child sitemap is listed with a <loc> tag inside a <sitemap> element. A sitemap index must also declare the sitemaps.org namespace. This validator follows sitemap indexes recursively, up to a safe depth, so you can validate an entire tree of sitemaps with one click.

Image, video, news and mobile extensions

Standard sitemaps support four extended namespaces that add media metadata to your URLs:

• Image sitemap — xmlns:image="http://www.google.com/schemas/sitemap-image/1.1". Each URL can declare one or more images with <image:loc> and optional <image:caption> and <image:title>.
• Video sitemap — xmlns:video="http://www.google.com/schemas/sitemap-video/1.1". Each URL can declare videos with thumbnail, title, description, duration, player location and more.
• News sitemap — xmlns:news="http://www.google.com/schemas/sitemap-news/0.9". For Google News articles, with publication date, title and keywords.
• Mobile sitemap — xmlns:mobile="http://www.google.com/schemas/sitemap-mobile/1.0". Used for feature phone URLs.

This validator detects each extension and reports the count of extended entries per sitemap.

Frequently asked questions