Free tool
Data Breach Checker
Enter a company domain to see whether it's appeared in known data breaches and dark-web leaks — which breaches, in what year, how many records, and exactly what data was exposed. The lookup is never logged or stored.
Enter a company or brand domain (for example example.com). The lookup runs server-side and is never logged or stored. Email-provider domains can't be checked.
Has this domain been in a data breach or on the dark web?
Enter a company or brand domain and the checker searches a public catalog of known breaches — the collections of stolen records that circulate on dark-web and darknet markets after an organization is compromised. If the domain matches, you'll see every breach it was involved in, the year, how many records were exposed, and the categories of leaked data: passwords, phone numbers, physical addresses, and more.
Why breach exposure matters
Leaked credentials are the fuel for most account takeovers and a large share of phishing. Once a breached dataset is on the dark web, attackers replay the credentials across other sites (credential stuffing) and use the breached company's name to craft convincing lures. Knowing which breaches touched a domain tells you which accounts to reset and which phishing themes to distrust. Learn the mechanics in the data breach, data leak, credential stuffing, and dark web glossary entries.
From a single check to continuous monitoring
This tool answers a one-time question for one domain. Organizations need the ongoing version: watching breach dumps and dark-web markets for leaked employee and customer credentials, then connecting that exposure to the lookalike domains and phishing pages attackers build from it. That's what dark web & AI monitoring does as a program.
Frequently asked questions
What is a data breach checker?
A data breach checker (also called a data leak checker or dark web exposure checker) tells you whether a company's domain has appeared in known data breaches — incidents where its user data was stolen and often leaked or sold on the dark web. Enter a domain and it lists which breaches affected it, when, how many records were exposed, and what data was involved.
How do I check if a domain has been on the dark web?
Enter the domain above (for example adobe.com). The tool searches a public catalog of known breaches — the same datasets that circulate on dark-web and darknet markets — and reports every breach tied to that domain, with the categories of data exposed: passwords, phone numbers, addresses, and so on. It can't see private, undisclosed leaks, so treat a clean result as reassuring rather than absolute.
Why check by domain instead of email?
Checking a domain answers the brand-protection question: has this company been breached, and what customer or employee data leaked? It avoids handling individual people's email addresses, and it's the right lens for evaluating a vendor, a partner, or your own organization's exposure.
What's the difference between a data breach and a data leak?
A data breach is the incident — attackers gain unauthorized access to a system and exfiltrate data. A data leak is the exposure of that data, often when the stolen dataset is published, traded, or sold on dark-web forums. In practice the terms overlap, and this checker surfaces both: breaches a domain was involved in and the leaked datasets that followed.
A domain shows breaches — what should the owner do?
Force password resets for affected accounts and require unique passwords, enforce two-factor authentication for staff and customers, and watch for phishing that name-drops the breached service. Then monitor the dark web for leaked credentials and brand impersonation tied to the exposure, because attackers turn leaked data into convincing lures.
How can a business monitor breach and dark-web exposure at scale?
Checking one domain is the manual version of continuous monitoring. For an organization, leaked employee and customer credentials, brand mentions, and impersonation surface across breach dumps and dark-web markets constantly. PhishEye's dark-web and AI monitoring watches those sources and ties exposure back to the domains and pages attackers use, so you can act before a leak becomes a phishing campaign.
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One domain is a spot check. We monitor continuously.
PhishEye watches breach dumps and dark-web markets for leaked credentials and brand exposure, and links them to the infrastructure attackers build next.