~/blog / detect-typosquatting

How to detect typosquatting of your brand domain

// published 2026-04-17

Typosquatting is when somebody registers a domain that looks like yours — g00gle.com, microsft.com, paypa1.com — and uses it to phish your users or your staff. The cost of finding out the hard way is a credential leak. The cost of checking proactively is one browser tab.

The three families of cousin domains

The signal that actually matters

Someone registering a typosquat costs them $10 and usually means nothing. Someone serving DNS for it — pointing it at a real IP or accepting mail at it — is where intent shows up. Look for:

  1. A record present — the cousin resolves to a real IP. Something is hosted there.
  2. MX records present — this is the strongest signal. Whoever set this up is prepared to receive email. That's a phishing front waiting to launch (or already active).
  3. Valid TLS cert in CT logs — they've gone to the trouble of issuing HTTPS. Takes active setup, not just a DNS panel.

How to find them in bulk

You could check each variant by hand (dig, nslookup, one at a time), or you can paste your domain into the Impersonation / Typosquat Watcher. It generates 120+ cousin variants, fires parallel DNS + MX probes, and shows you only the ones that are live.

The tool runs in ~5 seconds for the basic check. The deep scan (which also queries crt.sh for TLS certs on every variant) takes ~30 seconds and catches more.

What to do when you find live cousins

  1. Document. Screenshot the audit page. Note the registered_on date (WHOIS) and who's hosting them.
  2. Defensive registration for the most dangerous 2-3 variants. Yes, it's annoying. Yes, it's cheaper than a breach. Focus on keyboard-adjacent typos of your brand and the top 3 cousin TLDs.
  3. UDRP / URS filing if somebody's actively squatting with bad faith. ICANN has the procedure — slow, but works.
  4. Brand-monitoring subscription (MarkMonitor, BrandShield) for ongoing coverage if you're a named target. The Typosquat Watcher is a great free tool; if the risk is existential, you want paid continuous monitoring too.

Run the check now: /tools/impersonation-watcher. Paste your brand, see what's out there.


check_your_own_domain
Run the free Typosquat / Impersonation Watcher to diagnose this on any domain.
[ Open Typosquat / Impersonation Watcher ]
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