Is on4t.com valid?

on4t.com

on4t.com is a domain that should be blocked from sign-ups or registrations. Based on our analysis, you should block this domain. If a user is trying to sign-up using an e-mail on this domain, it's likely that it's a malicious or fraudulent attempt for some reason.

The best way to detect and block domains like on4t.com is to use the Check-Mail API, available for free, for all programming languages.

Raw API JSON response:

{
    "valid": true,
    "block": true,
    "disposable": false,
    "email_forwarder": false,
    "domain": "on4t.com",
    "text": "Looks like disposable \/ temporary",
    "reason": "Heuristics: T3",
    "risk": 99,
    "mx_host": "mail.on4t.com",
    "possible_typo": [],
    "mx_ip": "148.113.217.74",
    "mx_info": "Using MX pointer mail.on4t.com from DNS with priority: 5",
    "last_changed_at": "2025-07-23T16:29:24+00:00"
}