This is open-source, but I also offer a SaaS solution that has check-if-email-exists packaged in a nice friendly web interface.

If you are interested, find out more at Reacher. If you have any questions, you can contact me at

Get Started

3 non-SaaS ways to get started with check-if-email-exists.

1. HTTP Backend Using Docker (Popular Method ) [Full docs]

This option allows you to run a HTTP backend using Docker, on a cloud instance or your own server. Please note that outbound port 25 must be open.

docker run -p 8080:8080 reacherhq/backend:latest

Then send a POST http://localhost:8080/v0/check_email request with the following body:

    "to_email": "",
    "from_email": "", // (optional) email to use in the `FROM` SMTP command, defaults to ""
    "hello_name": "",    // (optional) name to use in the `EHLO` SMTP command, defaults to "localhost"
    "proxy": {                        // (optional) SOCK5 proxy to run the verification through, default is empty
        "host": "",
        "port": 1080,
        "username": "me",             // (optional) Proxy username
        "password": "pass"            // (optional) Proxy password
    "smtp_port": 587                  // (optional) SMTP port to do the email verification, defaults to 25

2. Download The CLI [Full docs]

Note: The CLI binary doesn’t connect to any backend, it checks the email directly from your computer.

Head to the releases page and download the binary for your platform.

> $ check_if_email_exists --help
check_if_email_exists 0.9.1
Check if an email address exists without sending an email.

    check_if_email_exists [FLAGS] [OPTIONS] [TO_EMAIL]

For more information click here.

Published by Tamil S

Tamil has a great interest in the fields of Cyber Security, OSINT, and CTF projects. Currently, he is deeply involved in researching and publishing various security tools with Kali Linux Tutorials, which is quite fascinating.

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