OSINTYourself

Username & Social Media Tracking

WhatsMyName

Open sourceDual-use
Passive ReconSocial MediaUsernamesWeb-Based

Enumerates a username's presence across sites.

WhatsMyName is a community-maintained dataset, kept as a single JSON file (wmn-data.json), that its README says lets you find out if a username exists across hundreds of websites. Each entry describes what URL to query and what a successful or "not found" response looks like; separate tools read the file and do the actual checking. For a site to be included it must be publicly accessible and its profile URL must contain the username. The README points to whatsmyname.app as a free, browser-based tool built on the dataset.

Dual-use tool. This tool can be used for research and investigation, and also to find, track or identify people without their consent. Listing it here is not an endorsement of either use.
Privacy note. WhatsMyName checks whether a username exists across hundreds of websites, so a username you reuse can be linked across the sites it covers. Its README says sites behind paywalls or login walls can't be checked, and that a site is only included if its profile URL contains the username.

Official site: https://whatsmyname.app

Source: https://github.com/WebBreacher/WhatsMyName

Last verified 2026-10-12.

Description rewritten from the vendor's own pages and checked against them. How entries are checked.

Guides that use this tool

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