Compare sitemaps before a website migration

1. Save an inventory before the change

Download the current URL sitemap before moving or rebuilding a site. Keep that original file alongside the proposed new sitemap so that you can distinguish an intentional removal from an accidental omission.

If the site uses a sitemap index, collect the relevant child URL sitemaps. The Sitemap Comparison Tool accepts a URL sitemap or a plain URL list; it does not fetch child files from an index. Sitemaps may omit useful pages, so also consider URLs from analytics, internal links, and other available records.

2. Compare URLs with deliberate normalization

Load the old and new lists into Sitemap Comparison. The report separates added, removed, and unchanged URLs. It compares membership; it does not fetch pages or tell you whether the content is equivalent.

Keep query parameters and trailing slashes distinct unless you have verified that the site treats those variants as the same page. Ignoring them can hide a real migration issue. Fragments are removed because they do not identify separate crawlable pages.

Old: https://example.com/guides/old-image-workflow
New: https://example.com/guides/image-optimization
Decision: redirect only if the new page serves the same need

3. Choose a relevant destination for each removed page

For a removed URL with a genuine replacement, enter the destination from the new sitemap and export the redirect mapping CSV. Review the mapping with the people responsible for the content before generating server rules.

Do not send every missing page to the homepage. When there is no useful replacement, an appropriate 404 or 410 response can be clearer. The comparison tool validates membership in the new list, but it cannot decide whether two pages are meaningfully equivalent.

• Map directly to the final destination where possible.
• Preserve valuable content before consolidating pages.
• Check destinations for accidental noindex or crawl blocks.

4. Prepare and review the redirect rules

Use Redirect Rules Generator to prepare rules in a format supported by your host. Follow the selected tool's input format: a mapping CSV is a review artifact, not automatically a ready-to-deploy configuration.

Run the proposed rules through Redirect Chain Checker to find chains and loops. That checker analyzes the rules you provide; verify the actual HTTP responses on staging or after deployment as well.

5. Check the live site after launch

Request a sample of old URLs and confirm the full redirect path, final status code, and destination content. Update internal links to point directly at the new URLs. Check canonicals, robots rules, and the new sitemap.

Submit the updated sitemap in Search Console and monitor indexing and performance. An unchanged URL in the comparison can still have changed content, broken rendering, or an unexpected response, so test important unchanged pages too.

• Keep a backup of the previous routing configuration.
• Track any unmapped URLs and unexpected errors.
• Retain the URL inventory for later migration checks.