SpamAssassin - Use this program to "Unspam" your mailbox(es).
RealValidito - Phone Validator | Free Phone Number Validation & Phone Number Lookup Service | Realvalidito
MailScanner - MailScanner is a open source email security system design for Linux-based email gateways.
Numverify - Global phone number validation and lookup API
Rspamd - Rspamd is an advanced spam filtering system that allows evaluation of messages by a number of rules...
Clearout Phone - Phone Number Validation - Accuracy Guaranteed, GDPR Compliant, Abuse Phone Number Checker, Real-Time API 99.999% Uptime - Free Trial With 100 Credits!