PhishSentry — Lookalike Domain Checker

PhishSentry checks one specific thing, and tells you exactly what it found. When you land on a site, it examines the domain name for the patterns attackers use to imitate brands you trust: - Character substitution — paypa1.com instead of paypal.com, g00gle.net, netf1ix.com - Brand names on domains the brand does not own — paypal-secure.com, fedexverify.com, login-steam.com - Homograph and internationalised spoofing — Cyrillic and Greek characters that render as Latin ones - Brand names in a subdomain of an unrelated site — paypal.account-services.net - Typosquats — a character doubled, dropped, or swapped: ppaypal.com, payapl.com, amazn.com - Brand names on low-reputation top-level domains Every warning states the reason. Instead of a confidence score you cannot interrogate, you get "'paypal' appears in the domain 'paypa1-secure.com', which is not owned by paypal." You can judge the reasoning yourself. WHAT IT WILL NOT DO This is a domain-similarity checker, and this listing is deliberately specific about that: - It does NOT detect phishing hosted on a legitimate platform under an unrelated subdomain — for example a credential form at a random subdomain of a free hosting service. Those domains are not imitations, and the domain name carries no evidence of the page's contents. - It does NOT scan page content, attachments, or downloads. - It is NOT a replacement for Google Safe Browsing, antivirus software, or your own judgement. Measured performance and every known limitation are published in the repository (EVALUATION.md), including the measurements that led to this scope. PRIVACY - Only the HOSTNAME is ever sent — never the path, query string, or page content. - A built-in list of widely-used domains is checked entirely inside your browser. Those hostnames are never sent anywhere at all, so most ordinary browsing never leaves your device. - The checking service is stateless. Hostnames are not stored and are excluded from its logs. - No accounts. No analytics. No third parties. No data is sold. OPEN SOURCE Extension and checking service: https://github.com/abhishekjaden/Phish-Sentry Detection is deterministic rules, not a machine-learning model, which is why each verdict can name its reason — and why known-good brand domains are allowlisted by construction rather than merely scoring low.