What it does
You give it two URL lists, your current site and your new one. It matches them in descending order of confidence and produces a redirect map you can hand to a developer, plus a separate list of everything it could not match.
Where you have a Search Console export, it uses it to rank the output by impressions, so the review time goes to the pages that would actually cost you something.
How it matches
| Tier | Method |
|---|---|
| 1 | Exact path, ignoring case, trailing slashes and index files |
| 2 | Exact final slug |
| 3 | Token overlap across the last two path segments plus the page title |
| 4 | No confident match, so it goes to the unmatched list |
Tier three is the useful one. It strips stopwords, dates, numeric ids and pagination markers, then compares what’s left, so /blog/2024/03/why-seo-matters.html finds /insights/why-seo-matters/ without anyone writing a rule for it.
The rule it enforces
Every old URL goes to the closest equivalent page, or it 404s deliberately. Those are the two acceptable answers.
The tool will never invent a destination. Anything it cannot match confidently goes into its own file with the nearest candidate and a score, for a person to accept or reject in a few seconds each.
That constraint is the whole point. Redirecting the leftovers to the homepage is the single most damaging shortcut on a migration, and Google’s own guidance warns that redirecting a large number of old URLs to the homepage may be treated as a soft 404, meaning the value does not transfer and the pages simply disappear.
What you get
- A redirect map as a CSV, with the method and confidence against each row so you can see which ones were judgement calls
- An unmatched list, ranked by impressions, so the decisions that matter come first
- A summary with the pre-launch checks, including any destination receiving an unusual number of redirects, which is how catch-alls get spotted
What it will not do
It won’t tell you whether a destination is genuinely the right equivalent. A tier three match at 0.6 confidence is a good guess, and it’s still a guess. The map is a starting point for a review, not a file to apply unread.
It also won’t check your redirects after implementation. Confirming every one resolves in a single hop is a separate step, and it’s the one people skip.
Before you launch
- Work down the unmatched list from the top
- Eyeball anything below 0.75 confidence
- Confirm every redirect resolves in one hop, since chains lose value and accumulate
- Update internal links to point at the new URLs rather than relying on the redirects
- Regenerate the sitemap from the new URLs only
- Leave the redirects in place. Google’s Change of Address guidance suggests at least 180 days, and there’s rarely a good reason to remove them at all
Related
This is the same tool used on client migrations. The service it supports is site migrations and domain and URL structure changes. Other tools are on the tools page.
FAQ
What format do the URL lists need to be in?
A CSV with a url, address or page column, which a Screaming Frog export already is, an XML sitemap, or a plain text file with one URL per line. A title column improves the fuzzy matching noticeably, so include it if you have one.
Why does it leave some URLs unmatched?
Because guessing would be worse than asking. An unmatched URL arrives with its nearest candidate and a score, so it takes a few seconds to accept or reject. A wrong redirect applied silently can sit there for years, and nobody ever goes looking for it.
Can I just redirect everything to the homepage?
You can, and it’s the shortcut that causes most migration damage. Google warns it may treat that pattern as a soft 404, so the value doesn’t pass. A deliberate 404 is more honest and handled better than a redirect to something irrelevant.
How long should redirects stay up?
Google’s Change of Address guidance suggests keeping them for at least 180 days. I would keep them permanently wherever the platform allows it, because old links carry on sending people for years afterwards, and taking them down is a self-inflicted loss for no gain.
Planning a migration?
The map is the easy part. Deciding what happens to the pages with no equivalent is where the traffic is won or lost. Get in touch before launch, or start with a free assessment.