Find the carrier of a phone number: who the number was assigned to, whether that carrier runs a mobile, landline or VoIP network, where the number was registered, and whether the number has been reported for scam calls. US and Canadian numbers are checked against the official numbering records (NANPA and CNAC); other countries against libphonenumber range data. Free, no signup.
5 free lookups a day. A 10-digit number is read as US/Canada. Numbers are not stored. A whole list: bulk phone number validator (carrier and carrier type columns).
A North American number has three parts: area code (NPA), exchange (NXX) and line number - 202-555-0143. Numbers are handed to carriers in blocks, and the records of who got which block are public:
The lookup takes the most specific record: the thousands block if the number sits in one, otherwise the code. It maps the legal entity to the brand you know and to the kind of network it runs.
Current data: 198,676 US central office codes, 666,256 thousands blocks pooled to another carrier than the code holder, 28,772 Canadian codes and 3,145 carrier entities. Reloaded weekly; NANPA publishes daily.
Since November 2003 US mobile users can keep their number when they switch carriers, and landline numbers move too. The numbering records do not change when a number is ported - the block stays with the carrier it was assigned to. So a number shown as T-Mobile may now be on Verizon. The live answer sits in the Number Portability Administration Center database, which is queried per number for a fee; free lookup tools that claim the current carrier either pay for that query or show the same allocation data as here.
MVNOs (Mint, Visible, Cricket, Google Fi and the like) mostly run on numbers from their host network or a wholesale carrier, so they show up as that carrier.
For US and Canadian numbers the numbering plan itself does not tell mobile from landline - the digits look the same. The carrier does: a block held by a wireless carrier is mobile, one held by a wholesale VoIP carrier (Bandwidth, Onvoy, Telnyx, Twilio, Peerless) is VoIP. VoIP numbers are cheap and anonymous to get, which is why sign-up and OTP flows flag them - the lookup adds a voip_line risk signal for those ranges.
Share of assigned numbers by carrier brand, from the same records (a code counts 10,000 numbers, a pooled block 1,000).
| Carrier | Network | Share of numbers |
|---|---|---|
| Onvoy (Sinch) | VoIP | 10.6% |
| AT&T | Landline | 10.3% |
| AT&T Mobility | Mobile | 9.5% |
| Verizon Wireless | Mobile | 8.9% |
| T-Mobile | Mobile | 7.9% |
| Verizon | Landline | 3.8% |
| Bandwidth | VoIP | 3.6% |
| CenturyLink (Lumen) | Landline | 3.3% |
| Lumen (Level 3) | Landline | 3.1% |
| Metro by T-Mobile | Mobile | 2.4% |
| Frontier | Landline | 2.1% |
| Bell | Landline | 1.8% |
The same check runs in code: GET /v1/phone/+12025550143 with your key returns carrier (brand) and carrier_details - legal entity, OCN, network type, rate center, assignment date and source - next to validation and scam-risk fields. Whole lists go through CSV upload with carrier and carrier_type columns. API docs.
"carrier": "Verizon Wireless",
"carrier_details": {
"name": "Verizon Wireless",
"legal_name": "CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA",
"ocn": "6006",
"type": "mobile",
"rate_center": "LOSANGELES",
"region": "CA",
"assigned_on": "2014-07-25",
"source": "nanpa"
}
Yes: 5 lookups a day here without signup. A free API key gives 1,000 lookups a month by API or CSV upload, no card.
The number was most likely ported, or the person is on an MVNO. The lookup shows the carrier the number block was assigned to; porting does not change those records.
No. Carrier lookup tells you the network, not the subscriber. Caller name (CNAM) is a separate, paid database we do not query.
For mobile numbers in many countries, yes - from libphonenumber range data (Globe in the Philippines, O2 in the UK). Landlines outside North America mostly have no carrier on record.
NANPA and CNAC publish their assignment files daily; we reload them weekly. A block assigned this week may take up to a week to show.
Same JSON via API - free 1,000 lookups a month. No card. Also: phone number validator, bulk CSV check.