First, you probably do have one
The convention is /sitemap.xml, and plenty of platforms ignore it. WordPress core has published its sitemap at /wp-sitemap.xml since version 5.5. Yoast and Rank Math both use /sitemap_index.xml. Shopify, Wix, Squarespace and Webflow all generate sitemaps automatically, at paths that are not always the obvious one.
So a 404 at /sitemap.xml is a statement about one URL, not about your site. The fastest way to settle it is to read your own robots.txt, because a Sitemap directive there is authoritative: whatever it points at is what you are telling crawlers to use.
Our sitemap checker looks in all the usual places and reads robots.txt, so it will find one if there is one.
- /sitemap_index.xml, common with Yoast or Rank Math
- /wp-sitemap.xml, WordPress core since 5.5
- /sitemap-pages.xml and siblings, some Next.js and headless setups
- The Sitemap line in /robots.txt, which overrides every guess
How much this actually matters
Less than most people assume, and it is worth being straight about that rather than manufacturing urgency.
Google's own documentation is blunt on the point: "Submitting a sitemap is merely a hint: it doesn't guarantee that Google will download the sitemap or use the sitemap for crawling URLs on the site." A sitemap helps discovery. It does not force indexing and it does not improve rankings.
That means a small site with clean internal linking loses very little by having no sitemap. Every page is reachable in a click or two, so a crawler finds everything anyway.
It matters more when the site is large, when internal linking is weak, when pages are deep in the structure, or when you publish something new and want it found quickly. If you recognise your site in that list, the missing file is worth fixing this week rather than this year.
If you genuinely do not have one
Do not hand-build a static file if you can avoid it. A sitemap you generate once is wrong the moment you publish anything, and nobody remembers to regenerate it.
On WordPress, check whether an SEO plugin is already producing one, and if not, core will be. On a hosted platform, look in the SEO settings rather than the file system, because you often cannot upload files at all. On a custom site, generate it in the framework: Next.js has a sitemap convention, and most others do too.
A one-off generator is the right answer only for a small static site that rarely changes. Ours will crawl up to 40 pages and hand you the XML if that describes you.
The failure that is worse than a 404
A 404 is at least honest. The nastier version is a sitemap URL that returns HTTP 200 with something that is not sitemap XML, usually an HTML error page or your app shell.
Nothing looks broken. The URL loads in a browser. Monitoring stays quiet. And every crawler that fetches it gets nothing usable, potentially for years.
If your checker reports valid XML, you are fine. If it reports a 200 that is not XML, treat that as more urgent than a 404, precisely because it is invisible.
Common questions
Is a missing sitemap.xml an SEO problem?+
Usually a minor one. Google describes a sitemap as a hint rather than a guarantee, and says submitting one does not ensure it will be downloaded or used. Discovery matters most on large sites, sites with weak internal linking, and for brand new pages.
Where else should I look before making one?+
/sitemap_index.xml, /wp-sitemap.xml, and the Sitemap directive in your robots.txt. WordPress core has produced a sitemap since 5.5, and Shopify, Wix, Squarespace and Webflow all generate one automatically.
Should I create a static sitemap.xml file?+
Only for a small site that rarely changes. A static file is out of date as soon as you publish, and nobody regenerates it. Prefer whatever your platform or framework generates automatically.
Will adding a sitemap improve my rankings?+
No. It helps search engines discover URLs. Ranking is decided by other things entirely, and Google is explicit that a sitemap is a hint rather than an instruction.
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