Build the URL inventory first
Crawl the current site and combine those URLs with analytics, search-console exports, backlinks, sitemaps, and known campaign links. Redirect planning based only on exported files misses addresses readers still use.
Map intent one address at a time
Send each old URL to the closest new answer. Avoid routing every removed page to the homepage or chaining through several historical locations. Keep query parameters only when the destination uses them.
- Use permanent redirects for settled moves.
- Preserve fragments when the corresponding heading survives.
- Return a real 404 or 410 when no replacement exists.
- Keep canonical URLs self-referencing on the new site.
Test before and observe after launch
Run the full map against a preview, then crawl the production host after DNS changes. Watch redirect failures, not-found traffic, index coverage, and high-value query movement. Keep the map versioned so later changes do not erase migration history.