How the SEO Scanner Works: Finding Dead URLs With the Wayback Machine

You lost traffic after your migration. So you did the sensible thing — you ran a redirect checker.

And it told you everything looks fine.

No broken links. No 404s. Green across the board. Meanwhile your organic traffic is still flat on the floor.

If that's you, the tool isn't lying. It's just looking in the wrong place.

Why your redirect checker says everything's fine

Here's the thing every live-site crawler has in common: it can only follow links that still exist.

It starts on your homepage, clicks through your menus, walks your collections and product pages, and reports back on everything it finds.

But the URLs killing your traffic aren't on your site anymore.

They vanished the day you migrated. /product/blue-widget/ doesn't link to anything now — it just returns a 404. A crawler that only follows live links will never even reach it. It doesn't know the page ever existed.

Google does, though. It still remembers every one of those old addresses — and it keeps knocking on doors that no longer open. That mismatch is the most common reason stores lose traffic after migrating.

Picture a store with 5,000 products. A live crawler sweeps the site and reports zero broken links. Meanwhile, Google is still trying to crawl 700 addresses that vanished during the migration — and finding nothing.

That gap — between what Google remembers and what your crawler can see — is exactly where post-migration traffic goes to die.

So how do you find a page that's already gone?

You need a record of your site from before the move. A list of every URL you used to have, whether or not it still exists.

That record already exists. It's called the Wayback Machine.

What the Wayback Machine actually is

Think of the Wayback Machine as a time machine for websites.

For years, a nonprofit called the Internet Archive has been quietly taking snapshots of public sites — including yours. Every snapshot is a copy of your store as it looked that day, right down to the addresses it was using.

Which means it also remembers URLs your current store has completely forgotten. Products you've since discontinued. Categories you reorganized. Blog posts from three years ago that still pull in backlinks.

It's the memory of your site that your current store no longer has.

Better yet, it's public. No login. No store access. No API.

How the scanner works backwards

Most tools start with your live site and look forward. Our scanner starts with your history and works backwards. Here's the idea in plain terms:

It rebuilds your old URL list. Instead of crawling your live store, it pulls your store's history out of the Wayback Machine — the addresses that existed before your migration.
It knocks on every old door. Each historical URL gets checked against your live Shopify store. Does it load? Redirect? Return a 404?
It flags the dead ones. Every address that now 404s — or limps through a redirect chain instead of one clean jump — gets pulled into a list. These are the pages leaking your rankings.
It suggests where each one should go. For each dead URL, the scanner matches it to the closest live page on your store and proposes that as the redirect target.

No store login. No app to install. No API keys. It runs entirely on public data — your history and your live site — and hands you back the list your redirect checker could never build.

What you actually get

A plain list of the URLs quietly costing you traffic, and where to send each one.

For every dead address, you see:

The old URL Google still remembers
What it does today (404, redirect chain, or loop)
A suggested redirect target on your current store

That's the whole redirect plan — the same one you'd spend a weekend assembling by hand from sitemaps and spreadsheets — built in a couple of minutes.

Run a free scan — no store access, and you'll have your list in about ninety seconds.

What to do with the list

The findings are only half the job. The other half is acting on them fast.

Take the list, open Shopify (Settings → Navigation → URL Redirects), and point every old URL at its match. Watch for the two traps that quietly undo good work: routing several hops through a chain, and dumping everything onto the homepage. One clean 301 per URL is the whole game. Our redirect checklist walks through that part step by step.

The sooner those 404s become clean redirects, the more ranking signal you claw back. Every week they stay live, a little more slips away for good.

Why we built it this way

There's no shortage of redirect checkers. Almost all of them do the same thing: scan your live site and tell you what's broken right now.

That's handy for catching a link you fat-fingered last Tuesday. It's useless for a migration, because the damage isn't a broken link on a live page — it's a whole layer of pages that stopped existing.

We wanted a tool for the second problem. One that doesn't ask "what's broken on your site?" but "what did your site used to have that Google still expects to find?"

Different question. Completely different list of answers.

The bottom line

If your migration cost you traffic, don't assume Google has already forgotten your old URLs. In many cases, it hasn't.

Finding those forgotten pages is usually the first step toward getting that traffic back.

Frequently asked questions

Q: Do you need access to my Shopify store? A: No. The scanner runs on public data only — the Wayback Machine's archive and your live storefront. There's nothing to install and no login to hand over.

Q: How is this different from a normal redirect checker? A: A normal checker crawls your live site and finds links that are broken today. It can't see pages that no longer exist anywhere on your store — and after a migration, those are the ones silently losing search visibility. This scanner rebuilds that missing layer from your site's history.

Q: What if my store isn't in the Wayback Machine? A: Most public stores with any real history are archived, often more thoroughly than owners expect. If your store is brand new or was blocked from archiving, there's less to pull — but for a site that lost traffic after a migration, the record is almost always there.

Q: How many URLs does the free scan check? A: The free scan covers your most important historical URLs — enough to surface the redirects that matter most. Larger catalogs can go deeper with a full audit.

Q: Is the Wayback Machine data actually reliable? A: It's a record of what existed, not a guess. If an address shows up in the archive, it was a real, live page at some point — which means Google very likely indexed it too.