How Do You Know if a Number is VoIP?

Used by businesses all over the world, voice over Internet Protocol (VoIP) is a technology that converts phone calls into digital signals and transmits them through the internet.

With the increasing popularity of VoIP phone numbers, it’s likely that you’ve already received a call from one without even noticing. So how do you tell if a number is VOIP?

One option is to use online tools such as freecarrierlookup.com to perform a Local Routing Number (LRN) lookup. An LRN lookup will tell you the carrier that owns the number.

If the carrier is something like Neutral Tandem, Bandwidth, or Google, it’s likely a VOIP number. Landline carriers will typically be major providers such as AT&T or Verizon.

Another way to identify a VoIP number is to listen to the call quality. VoIP calls may have distinct differences compared to landline calls, such as a slight delay or lower call quality.

You could also attempt a CNAM lookup to learn more about the caller. CNAM stands for Caller ID Name and, if available, surfaces information about the caller’s name and location.

Your final option is  to use a reverse lookup service. This service will tell you if the caller is a VoIP number, who owns the number, and their address, if the information is known.

But the most accurate way we’ve found is a combination of LRN and listening closely for the telltale audio signs a call is being routed through the internet and not a traditional mast.