Number lookup API

Number Lookup from Telnyx is a service that allows you to input a number and receive back information about the number carrier and caller ID.

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Yes! Use our Carrier Lookup for international numbers to see where a number is registered, number type, carrier name, Mobile Country Code (MCC), Mobile Network Code (MNC) and more.

LRN, or Local Routing Number is an identification for a telephone switch for the purpose of routing telephone calls through the PSTN in the U.S. With LRN, you’ll know exactly how calls to the number will be billed on tariff pricing.

Head over to our Identity Services and Data pricing page for more details, or speak to one of our experts about custom pricing options.

Number lookup and phone number validation are closely related but serve slightly different purposes. Phone number validation checks whether a number is formatted correctly and reachable. Number lookup goes further - it returns real-time carrier data, line type, CNAM, and portability status. Most businesses use both together: validate the format, then lookup the carrier and line type to make routing or messaging decisions.

HLR lookup (Home Location Register) is a telecom query that returns the live status of a mobile number from the carrier's subscriber database. It tells you whether a mobile number is active, which carrier currently serves it, and whether it has been ported. HLR lookup provides more accurate mobile number data than static database lookups because it queries the network in real time.

Yes. Number lookup queries live telecom databases to return the current status of a number. For mobile numbers, HLR lookup confirms whether the number is active on the network. For landlines, the carrier and line type data indicate whether the number is in service. This is more accurate than format-only validation.

Carrier lookup sends a query to telecom databases - including the HLR for mobile numbers - and returns the carrier currently serving the number. Because millions of numbers have been ported between carriers, the lookup reflects the actual serving carrier today, not the original carrier. Results return in milliseconds via REST API.

Line type intelligence identifies whether a phone number is mobile, landline, or VoIP. This matters because each line type has different capabilities - landlines can't receive SMS, VoIP numbers are higher fraud risk, and mobile numbers support both voice and messaging. Line type lookup helps you route communications correctly and avoid wasted spend.

Yes. The Number Lookup API supports bulk lookups for high-throughput use cases. You can validate and enrich databases of millions of numbers programmatically. Each lookup is billed per dip ($0.0015 per LRN dip), with volume discounts available for high-volume customers.

SMS pumping fraud is when bad actors send SMS to premium-rate numbers they control, generating revenue at your expense. Number lookup prevents it by identifying line type and carrier in real time - if a number is VoIP, recently ported, or from a high-risk carrier, you can block or challenge the message before it's sent. This saves money on fraudulent messages and protects your sender reputation.