Email format

Email Format (email-format.com) is a reference database that documents the email address naming conventions used by thousands of organizations worldwide. By searching for a company or domain, investigators can identify the specific email format that organization uses — whether first.last@, flast@, firstname@, or other patterns — enabling systematic generation of valid email addresses for any individual known to work there.

For OSINT investigators conducting corporate investigations, knowing a target organization's email format is a fundamental capability. Once the pattern is established, any person known to work at the organization (from LinkedIn, conference speaker lists, press releases, or other OSINT sources) can have their likely email address generated and then validated through email verification tools.

The database is built from community contributions and verified email addresses, meaning the patterns it documents are derived from real, confirmed organizational addresses rather than speculation. Pattern confidence is typically high for major corporations and well-documented organizations.

Corporate email enumeration workflow: identify target organization's domain via OSINT, look up the email format pattern on Email Format, cross-reference with a staff list derived from LinkedIn or other sources, generate candidate email addresses for each identified individual, validate through Email Checker or Email Hippo, and feed confirmed addresses into breach databases and social media searches.

For penetration testing engagements, confirmed corporate email addresses are used in spear-phishing simulations, where realistic targeting requires accurate email address knowledge. For OSINT investigations, they provide verified pivot points for searches across platforms that use email addresses as account identifiers.

Email Format also allows reverse lookups — entering a known email address can confirm or reveal whether it fits the documented organizational pattern, which helps assess whether a claimed email address is consistent with that person's alleged employer.

Record the organization, identified email format, and source confirmation in case documentation.