Import your accounts once. After that, every page answers the question itself — a small marker says whether you're already on it. No server, no upload. There is nothing of yours for us to lose.
You open a site. It looks familiar. Was it this email? Did you use Google? You click sign up and it says the address is already registered — then you're stuck resetting a password for a site you barely remember.
Export from Chrome, Edge, Bitwarden, or 1Password. Import the CSV. Nothing is copied to a server — there isn't one.
Browse normally. A marker reads on it, not in your list, or muted. You don't open the extension to ask — you just see it.
Pro covers dead-weight accounts, overlapping subscriptions, and a cleanup queue. See pricing.
There are good tools in this space. The honest difference is who does the remembering.
Private and local can still be excellent. The catch is structural: you have to remember to record it. The account you forgot is the one you never wrote down.
After a single import, the answer shows up on the page — no lookup step, no habit to maintain. We're reading a list you already have.
Bitwarden and 1Password are better at logging in — use them for that. We answer a different question: do I even have an account here? Importing from them is the main onboarding path.
Some extensions track which Google/Apple identity you used. Narrower. We cover every entry in your imported list without reading login history.
Gmail authorization can find more accounts — and means handing over your inbox. We will never ask for that.
Don't trust a slogan — verify it. About forty seconds in DevTools is enough.
We don't call Google (or other) favicon proxies. That would leak every domain you visit. We use the page's own icon or a local tile.
No cookies, webRequest, or history permission.
Legal wording lives on the privacy page — use that URL for the Chrome Web Store listing.
Forever, no card.
It reads the list you imported. If a domain is in your CSV, you'll see the marker here. If not, you'll see not in your list — a prompt to check, not proof you never signed up.
No. There is no SignupMap server that receives your vault. Data stays in chrome.storage.local. Keep your CSV backup.
No. Browser extensions cannot see mobile app registrations. Be wary of services that match breach dumps.
Not yet — until a public repository exists, treat that as no. Verify via permissions, DevTools, and offline use instead.
Matching never needs the network. Wording is deliberately narrow: optional tools like a HIBP page would live separately and disclose before sending anything.
Chrome Web Store — no SignupMap account required.
Chrome password manager → Export, or Bitwarden Tools → Export. Drag into SignupMap.
The marker should match within about a second.