osintverse-community/mailcat
Finds existing email addresses for a nickname across 25+ mail providers
Takes username → finds email
No key · Python wheel
No key · Python wheel
Verified publisher
Find email addresses from a username
5 tools. 2 run with ot in a sandbox on Windows, macOS and Linux; 3 with otlite on Linux and macOS, no Docker. Compare them side by side ↓
People often use the same handle as the local part of their email address, and developers leave an address in every git commit they push. These tools check which mail providers have a mailbox for a handle, read the addresses from a GitHub user's public commits and keys, and find linked accounts that expose an address.
With ot, in a sandbox
All username tools →Windows, macOS and Linux, with Docker or Podman. Each tool runs in a read-only container that can reach only the sites it declares, and every result comes back in the same JSON shape.
osintverse-community/osgint
Looks up a GitHub user's public profile, SSH and GPG keys, and email addresses from their commits
Takes username → finds account, email, person, url
No key · Docker
No key · Docker
Verified publisher
ot install osintverse-community/mailcat osintverse-community/osgintInstalls the first 2 in one go; ot auto u:… then runs every installed tool that takes an username and saves the results. No ot yet? Install it in one line.
Without Docker, with otlite
All otlite tools →Linux and macOS. otlite installs each one with pip or git into its own virtualenv, pinned to a version it has tested: otlite install linkook.
- LinkookAn OSINT tool for discovering linked social accounts and associated emails across multiple platforms using a…Takes username, email
- ZenFind email addresses of GitHub users, repositories and organizationsTakes username, URL
- NeutrOSINTCheck if an email address or username exists on ProtonMailTakes email, username
The 2 registry tools side by side
| osintverse-community/ | None | Online, passive | Yes | Python | No reports yet | fewer than 10 | |
| osintverse-community/ | account, email, person, url | None | Online, passive | Yes | Docker | No reports yet | fewer than 10 |
Facts from each tool's manifest and what people report about whether it works. "Reaches" says whether a run stays offline, reads public sources, sends requests about the target, or may notify them.
How to find email addresses from a username
- Check which providers have the handle as a mailbox (mailcat, and NeutrOSINT for ProtonMail).
- If the handle is on GitHub, read the addresses from the user's commits (osgint, Zen).
- Confirm each address with a registration check on the email page before relying on it.
Every registry tool here runs on your machine in a sandbox, and ot auto u:… runs all the installed ones on one value.
Before you run one
Does mailcat send email?
No. It asks each provider's API or mail server whether the mailbox exists without delivering a message, so the owner isn't notified.
Why can GitHub show someone's email?
Every git commit records an author address. Unless the author set GitHub's no-reply address, pushing commits to a public repository publishes it, and the GitHub API returns it.
Do these tools send my search anywhere?
No. ot runs each tool on your own machine in a read-only container that can only reach the sites the tool declares, and results stay in your results folder. The registry only counts installs.
Do I need an API key?
Most tools here work without one; the row says "Key required" when one is needed, and ot keys set stores it in your OS keychain so only that tool's container sees it.