RealValidito - Phone Validator | Free Phone Number Validation & Phone Number Lookup Service | Realvalidito
Truecaller - Find a person by a name or phone number worldwide for free using Truecaller.
Numverify - Global phone number validation and lookup API
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Clearout Phone - Phone Number Validation - Accuracy Guaranteed, GDPR Compliant, Abuse Phone Number Checker, Real-Time API 99.999% Uptime - Free Trial With 100 Credits!
CallerSmart - CallerSmart is an application that is basically used for the purpose of looking up mystery phone numbers for free.