Free tool · line type

VoIP number checker

Find out what kind of line a phone number belongs to: mobile, landline, VoIP, toll-free, premium rate or shared cost.

What you get

VoIP numbers from dedicated VoIP ranges
Mobile, landline, toll-free, premium rate, shared cost, pager
Valid or invalid for the country
Country, calling code and all formats

Private by design

The check runs in your browser with Google's libphonenumber data. The numbers you enter are not sent to our servers or stored.

Building this into an app? Use the Carrier and line type lookup API and its validate endpoint documentation.

Line types explained

Line type	What it means
Mobile	A number issued to a mobile network. Receives calls and SMS.
Landline	A fixed-line number tied to a geographic area.
Landline or mobile	Shared ranges (US, Canada and others); the number alone does not tell.
VoIP	A number from a range reserved for internet telephony.
Toll-free	Free for the caller, e.g. 0800 or 1-800.
Premium rate	Costs the caller extra, e.g. 0900.
Shared cost	Cost split between caller and receiver.

Detecting VoIP numbers at scale

The free checker covers numbers from VoIP-specific ranges, and so does the API: its number_type field is voip for numbers from those ranges. To check every sign-up automatically, call the numlookupapi API in your sign-up flow and use line_type and number_type to decide whether a number is mobile, landline, VoIP or something else. VoIP services that hand out ordinary landline or mobile numbers cannot be detected from the number.

Frequently asked questions

How can I tell if a number is VoIP?

In many countries VoIP services get numbers from dedicated ranges, e.g. 056 in the UK or 032 in Germany. The checker detects these ranges. VoIP providers can also use regular landline or mobile numbers. Neither a range check nor the numlookupapi API can spot those, because the number looks like any other landline or mobile number.

Why do businesses check for VoIP numbers?

Virtual numbers are cheap to create in bulk, so they are common in fake sign-ups, promotion abuse and fraud. Many companies require a mobile number for two-factor authentication or flag VoIP numbers for review.

What does 'landline or mobile' mean?

In the US, Canada and a few other countries, landline and mobile numbers share the same ranges, so the number alone cannot tell them apart. The numlookupapi API looks the number up in its numbering-plan database, whose line_type often tells mobile and landline apart where the number alone cannot.

Can text messages be sent to VoIP numbers?

Some VoIP numbers receive SMS, many do not. Toll-free, premium rate and pager numbers generally cannot receive SMS. Check the line type before sending to avoid failed messages.

Phone number API

Validate numbers like this in your app

numlookupapi checks any phone number worldwide in one request and returns validity, line type, carrier, location and every standard format as JSON.

Read the documentation

100 free requests every month. No credit card required.

GET https://api.numlookupapi.com/v1/validate/+12069220880

{
  "valid": true,
  "number": "12069220880",
  "local_format": "2069220880",
  "international_format": "+12069220880",
  "country_prefix": "+1",
  "country_code": "US",
  "country_name": "United States of America",
  "location": "Seattle",
  "line_type": "landline",
  "e164_format": "+12069220880",
  "national_format": "(206) 922-0880"
}

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