XML sitemap

What goes in an XML sitemap?#

An XML sitemap should list every canonical, indexable URL you want in search — each in a <loc> tag, with an optional <lastmod> date of its last significant change — and nothing else: no redirects, no noindex pages and no parameter duplicates.

<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
  <url>
    <loc>https://www.example.com/pricing</loc>
    <lastmod>2026-09-18T09:30:00+00:00</lastmod>
  </url>
  <url>
    <loc>https://www.example.com/blog/launch-checklist</loc>
    <lastmod>2026-09-02T14:05:00+00:00</lastmod>
  </url>
</urlset>

• Absolute, canonical URLs. Google crawls URLs “exactly as listed” and treats sitemap inclusion as a weak canonical signal, so list the version your canonical tag points to.
• lastmod only when it’s true. Google uses it only when it’s “consistently and verifiably” accurate, and means the last significant change — main text, structured data or links, not a footer tweak.
• Skip priority and changefreq. Google and Bing both say they ignore them.
• Point engines to it with a Sitemap: line in robots.txt, and submit it in Google Search Console and Bing Webmaster Tools.

# Any crawler that reads robots.txt can find the sitemap here
Sitemap: https://www.example.com/sitemap.xml

How big can an XML sitemap be?#

An XML sitemap can hold up to 50,000 URLs or 50 MB uncompressed, whichever comes first; larger sites split their URLs across several files and list them in a sitemap index, which can reference up to 50,000 child sitemaps.

<?xml version="1.0" encoding="UTF-8"?>
<sitemapindex xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
  <sitemap>
    <loc>https://www.example.com/sitemap-pages.xml</loc>
    <lastmod>2026-09-18T09:30:00+00:00</lastmod>
  </sitemap>
  <sitemap>
    <loc>https://www.example.com/sitemap-blog.xml</loc>
    <lastmod>2026-09-20T07:00:00+00:00</lastmod>
  </sitemap>
</sitemapindex>

Splitting by section — pages, blog, docs, products — pays off even below the limits. Search Console’s Page indexing report can be filtered by submitted sitemap, so a blog sitemap with half its URLs unindexed points you straight at the problem.

Placement matters too: a sitemap only covers URLs under its own directory, which is why Google recommends putting it at the site root. Bing’s 2025 guidance adds that one index can reference 50,000 child sitemaps, enough for 2.5 billion URLs — a ceiling no small site will meet.

Do you need an XML sitemap?#

Google says a well-linked site of about 500 pages or fewer may not need an XML sitemap, but new sites with few external links, large sites and media-heavy sites benefit — and because a sitemap costs almost nothing, most sites should keep one anyway.

Do AI search engines use XML sitemaps?#

Among AI search engines, Bing is the most explicit about XML sitemaps: it calls lastmod a key signal for deciding what to recrawl for AI-powered search. Google uses sitemaps for the index behind AI Overviews and Gemini, while OpenAI, Anthropic and Perplexity haven’t said whether their crawlers read them.

Bing — Copilot, and ChatGPT's Bing pathHelps

Bing’s July 2025 guidance: “The lastmod field in your sitemap remains a key signal,” helping it prioritize URLs for recrawling — or skip them when nothing changed. It asks for full date-and-time values.

Google — AI Overviews, AI Mode, GeminiHelps

Sitemaps aid discovery and recrawl scheduling for the Search index all three draw on. Google trusts lastmod once it proves accurate.

OpenAI — OAI-SearchBotUnconfirmed

OpenAI doesn’t say whether its search crawler reads sitemaps.

Anthropic and Brave — ClaudeUnconfirmed

Not documented. Brave discovers pages through its crawler and browser users’ visits, so ranking on Google and Bing feeds it indirectly.

PerplexityUnconfirmed

Not documented; its crawler schedules revisits by predicted importance and update frequency. A sitemap referenced from robots.txt costs nothing.

The upshot: one honest sitemap serves every engine that reads it and harms none that don’t. For Bing, pair it with IndexNow — Microsoft describes the two as complements, sitemaps for full coverage and pings for URL-level changes. Honest dates matter beyond Bing too: AI answers lean on content freshness, and a lastmod that matches the visible updated date keeps your signals consistent.

Common mistakes with XML sitemaps#

The most common XML sitemap mistakes are listing URLs that redirect, return 404 or carry noindex, stamping every lastmod with today’s date, and forgetting the file after a migration so it keeps advertising old URLs.

Related terms#

• Technical SEOIndexNowAn open protocol that lets a website notify participating search engines, led by Microsoft Bing, the moment a URL is added, updated or deleted, instead of waiting to be recrawled — Google does not use it.Read the entry
• Technical SEOIndexingThe step in which a search engine processes a crawled page and stores it in its searchable database; only indexed pages can rank, or be retrieved for AI answers built on that index, and being crawled does not guarantee being indexed.Read the entry
• Technical SEOCrawl budgetThe number of URLs a search engine is willing and able to crawl on a site in a given period, set by how much load the server can take and how much the engine wants the content — a real constraint mainly for large or fast-changing sites.Read the entry
• Technical SEOCanonical tagAn HTML link element (rel="canonical") that tells search engines which URL is the preferred version of a page reachable at several addresses, consolidating its ranking signals onto that one URL — a strong hint, not a command.Read the entry
• AI crawlersrobots.txtA plain-text file at a site’s root that tells crawlers which paths they may fetch, rule by rule for each user agent — a voluntary standard that reputable search and AI bots follow, which controls crawling but not whether a URL gets indexed.Read the entry
• GSCMeasurementGoogle Search ConsoleGoogle’s free tool for site owners that reports how a site performs in Google Search — queries, impressions, clicks, position and indexing — and since 2026 it also reports impressions in Google’s generative AI features and lets owners opt out of them.Read the entry