Check That Phone APIs
Real-time phone validation API: carrier lookup, line type detection (mobile, landline, VoIP, toll-free), number portability, deliverability check, LRN and GeoIP timezone. Single GET for U.S. and Canadian numbers. Use for SMS optimization, TCPA and 10DLC compliance, fraud prevention, and contact validation.
Check That Phone V4
Validate a U.S. or Canadian phone number and optionally provide subscriber IPv4 or IPv6 for GeoIP and timezone. Returns carrier name and type, line type (mobile, landline, VoIP, toll-free), portability status, deliverability, blacklist screening, and when IP is provided: GeoIP location, timezone, and Local Routing Number (LRN) for call or SMS routing. One GET returns 20+ fields for signup flows, messaging, and compliance checks.