Holehe
Checks whether an email is registered on 120+ sites via password-reset flows.
Holehe is an open-source tool that checks if an email address is registered on over 120 different websites by utilizing password reset functions. It allows researchers to identify which online services are associated with a specific email address without directly accessing user accounts. This capability supports legitimate investigations into digital footprints and potential account exposure.
Dual-use tool. This is capable of legitimate research (journalism, security, due diligence) and of harassment or stalking. Listing it here is not an endorsement of either use.
Privacy note. Reveals which services your email is registered on — check your own exposure.
Official site: https://github.com/megadose/holehe
Source: https://github.com/megadose/holehe
Last verified 2026-08-31.