An XML sitemap is a file in Extensible Markup Language (XML) format that contains a structured list of all relevant URLs on a website. It is used by search engines such as Google, Bing and others as a guide to efficiently discovering the contents of a web presence, to crawl and to index. In essence, it is a kind of „map“ or „table of contents“ specifically for web crawlers, which helps them to better understand the structure of a website and ensure that no important pages are overlooked.
Structure and functionality of an XML sitemap
The basic structure of an XML sitemap is clearly defined. Each sitemap file begins with the XML declarator and is extended by the root element <urlset> enclosed. Within this element, each individual relevant URL of the website is displayed as a <url>-element.
At least every <url>-element must have a <loc>-tag, which specifies the full URL of the page. Optionally, other tags such as <lastmod> (date of the last change in W3C date format, e.g. 2025-10-22), <changefreq> (estimated frequency of changes, e.g. daily or weekly) and <priority> (relative priority of the URL on a scale from 0.0 to 1.0). However, it should be noted that Google uses the information on changefreq and priority often interpreted as hints and not as strict instructions.
A simplified example of the structure of an XML sitemap:
https://www.ihre-agentur.de/
2025-10-22
daily
1.0
https://www.ihre-agentur.de/leistungen/seo/
2025-09-15
weekly
0.8
The encoding of the file must be UTF-8 in order to ensure correct processing of all characters.
Significance for search engine optimization (SEO)
For the Search engine optimization an XML sitemap is a valuable technical tool, even if it has no direct effect on the Ranking has. Its main benefit lies in supporting the crawling and indexing process.
The use of an XML sitemap is particularly advantageous for:
- New websitesSearch engines can discover new content more quickly and include it in their index because the sitemap provides a direct reference.
- Large or complex websites: For extensive or deeply nested structures, the sitemap helps the crawlers to find all relevant pages that may not be optimized. internally linked are.
- Websites with isolated contentPages that receive few internal links or are generated dynamically benefit from being explicitly mentioned in the sitemap.
- Media contentSpecial sitemaps can be created for images, videos or news articles to provide search engines with more detailed information on these media types and facilitate their indexing.
After creation, the XML sitemap is usually submitted to the search engines, for example via the Google Search Console or the Bing Webmaster Tools. This speeds up processing and offers webmasters the opportunity to monitor the indexing status and identify possible errors.
There are certain guidelines for the size and number of XML sitemaps: A single uncompressed sitemap file may be a maximum of 50 MB in size and contain up to 50,000 URLs. For websites that exceed these limits, it is common practice to split the URLs into several sitemaps and bundle them into a sitemap index file, which is then submitted to the search engines. It is crucial that the URLs listed in the sitemap are exclusively canonical URLs with an HTTP status code 200 (OK) and do not contain any redirects or error pages.
