Email Breach Check
See whether an email address appears in known data breaches, which sources leaked it, and what categories of data were exposed. Breach data Powered by LeakCheck; we never see or show the leaked data itself.
# free & rate-limited · no signup · live results from the same engine as the API
Since the engine is the same one the API runs, a key does not buy you a better answer. It buys volume, bulk jobs and a signed receipt.
Three quick steps
Breach index is queried
The address is checked against a public breach index (Powered by LeakCheck), alongside our full verification: syntax, MX, SMTP mailbox, reputation.
Read the exposure
Record count, the breach sources with dates, and which data categories were exposed — passwords, addresses, phone numbers.
Source-level detail
Not a yes/no: the breach sources are named with dates, newest first.
Exposed-data categories
Know if passwords, dates of birth, or addresses were in the leak — without ever seeing the leaked values.
Full verification included
The same check also runs syntax, MX, live SMTP mailbox and domain reputation — one lookup, whole picture.
Honest when unknown
If the breach index is unreachable, the row says nothing rather than guessing. Your check still completes.
Who uses it
Account-takeover triage
A password-exposed address deserves a reset prompt and MFA nudge at login.
Signup review
Breach history says an address is old and real — useful context next to the fraud signals.
Personal hygiene
Check your own addresses and rotate passwords where exposure includes them.
Security teams
Batch-check a company's addresses through the API's bulk jobs.
FAQ
Where does the breach data come from?
From LeakCheck's public breach index ("Powered by LeakCheck"). We send only the address being checked, receive breach source names and exposed-data categories, and never receive or display the leaked data itself.
Does appearing in a breach mean the address is dangerous?
No — it mostly means the address is old enough to have history. That is why our signup-risk score does not punish breach presence. A recent password exposure is the part worth acting on.
Why do some checks show no breach row?
The breach index is a free external service with a rate limit. When it is unreachable we omit the row rather than guess; the rest of the verification still answers.