Where it is and what is in it
Shopify publishes a sitemap index at /sitemap.xml on every store, with no setup required. It is an index rather than a flat list, so the loc entries inside it point at other sitemap files rather than at pages.
The children are split by resource type, typically products, collections, pages and blog posts, each in its own file. That split is genuinely useful, because it gives you per-section reporting in Search Console: you can see that products are indexing well while collections are not.
Because it is an index, a checker that does not follow indexes will report zero URLs. That is a limitation of the checker, not a problem with your store. Ours follows it.
What you cannot do
This is where most Shopify sitemap questions end up, and the answer is usually that you cannot, by design.
You cannot edit the file, add URLs to it, remove individual entries by hand, or change how it is split. On the standard plans you also cannot edit robots.txt through the admin, though Shopify has allowed robots.txt.liquid customisation on newer stores.
This frustrates people, and it is mostly the right trade. A generated sitemap is always current, which is more than can be said for most hand-managed ones. What you lose is control you probably should not be exercising manually.
How to actually remove something
The rule: change the resource, not the sitemap. The sitemap reflects what is published, so make the thing unpublished.
For a product you do not want listed, unpublish it from the online store sales channel. It leaves the sitemap because it is no longer public, which is the correct outcome and also stops customers reaching it.
For a page, unpublish it or set it to hidden. For a collection, the same applies.
If you want a page to stay reachable but out of search, that is a noindex question rather than a sitemap question, and on Shopify it means editing theme.liquid to add a robots meta tag conditionally. Be aware that a page which is noindex should not be in a sitemap, so the two need to agree.
Things that surprise Shopify owners
Three that come up repeatedly.
Variant URLs. Shopify produces URLs with variant parameters, and those are generally not in the sitemap, which is correct: they are the same product page with a selection applied, not separate pages.
Collection pagination. Paginated collection pages are usually excluded, and that is also correct. You want the collection indexed, not page seven of it.
Duplicate product paths. Shopify can serve the same product under a collection path and a bare product path. The sitemap lists the canonical one, and if you are seeing both in search, that is a canonical tag question rather than a sitemap fault.
Common questions
Where is my Shopify sitemap?+
At /sitemap.xml on every store, generated automatically. It is a sitemap index whose children cover products, collections, pages and blogs separately.
Can I edit my Shopify sitemap?+
No. It is generated and cannot be edited, have URLs added, or be split differently. The upside is that it is always current.
How do I remove a product from the sitemap?+
Unpublish it from the online store sales channel. The sitemap reflects what is published, so changing visibility is the supported way to remove something.
Why does my sitemap checker say zero URLs?+
Because Shopify's /sitemap.xml is an index rather than a flat list, and a checker that does not follow indexes sees entries pointing at other files rather than at pages. Nothing is wrong with your store.
Are variant URLs in the sitemap?+
Generally not, and that is correct. A variant URL is the same product page with a selection applied rather than a distinct page.
Sources