Can a phone number lookup API tell me who owns a number?

No. The Digital Footprint phone number lookup returns facts about the number - validity, carrier, line type, VOIP class and which platforms it is registered on - never a name, address or account contents. It is not a reverse phone directory.

Which platforms can be checked by phone number?

A phone number can currently be checked on WhatsApp, Telegram, Facebook, Instagram and X (Twitter). WhatsApp and Telegram run by default, and any of the others can be named per request. Each platform is priced separately on the public rate card and billed only when it runs.

Can a phone lookup detect VOIP numbers?

Yes. The phone module returns the line type and a VOIP class that separates fixed VOIP (a business line tied to an address) from non-fixed VOIP (a number anyone can create in an app). Non-fixed VOIP is the category behind most disposable signup numbers, and it is one of the named risk signals.

Does the phone lookup return a risk score?

Yes. The phone module returns a 0-100 risk score that is the sum of the named signals that fired - for example an internet (VOIP) number - and each signal is listed with its points. Accounts can switch default rules off, change their points, or add their own rules.

Is a phone number lookup free to try?

There are free lookups to start, no card required. After that, phone intelligence and each phone platform are priced per check on the public rate card, with no subscription needed.

Phone number lookup API: what one request tells you about a number

Updated 2026-09-29

A phone number lookup API takes a number and returns what can be verified about it. Here that is two things in one request: phone intelligence - validity, formats, carrier, line type, VOIP class and a risk score - and which platforms the number is registered on (WhatsApp, Telegram, Facebook, Instagram and X (Twitter)). Every fact is confirmed or left out, never guessed.

What a phone number lookup returns

Two modules answer for a number. The phone module returns validity, E.164 and national formats, country, carrier, line type and VOIP class - plus SIM-swap and call-forwarding risk detection on higher plans where the carrier supports them - and a risk score with its signals. The footprint checks which platforms the number is registered on, one row per platform with registered and checkedAt. Ask for either or both.

POST /v2/lookup

curl -X POST "https://api.digifootprint.dev/v2/lookup" \
  -H "Authorization: Bearer dfp_your_key" \
  -H "Content-Type: application/json" \
  -d '{"phone": "+14155552671", "checks": {"footprint": true, "phone": true, "riskSignals": true}}'

Response (abridged)

{
  "lookupId": "9f2c41d0-...",
  "footprint": {
    "platformsChecked": 2,
    "matches": 1,
    "results": [
      { "platform": "whatsapp", "registered": true, "identity": "phone", "checkedAt": "2026-09-29T10:14:02.118Z" }
    ]
  },
  "phone": {
    "number": "+14155552671",
    "valid": true,
    "e164": "+14155552671",
    "nationalFormat": "(415) 555-2671",
    "countryCode": "US",
    "carrier": "T-Mobile USA",
    "lineType": "mobile",
    "isVoip": false,
    "risk": { "score": 0, "signals": [] }
  },
  "risk": { "score": 0, "signals": [] }
}

Send the number with its country code. Sending it as query works too: the type is detected, so one endpoint and one key serve email, phone, IP and username lookups. Every field is in the phone reference.

Platform checks by phone number

A number can be checked on WhatsApp, Telegram, Facebook, Instagram and X (Twitter). The default set (WhatsApp and Telegram) runs when you name nothing; name others in checks.footprint.phone.platforms. Each platform is billed only when it runs, so a check limited to WhatsApp costs a WhatsApp check and nothing more. The WhatsApp number check guide covers the request in detail, and prices are on the rate card.

Reverse phone lookup API: what it will not tell you

It will not tell you who the number belongs to: no name, no address, no photos, nothing from inside any account. It will not call a number fraudulent - the risk score is the total of named, auditable signals, and a VOIP line is a reason to look closer, not a verdict. And where a fact could not be established the field is null, and a platform that could not be checked is left out rather than reported as registered: false.

Where a phone lookup fits alongside email and IP

A v2 request can carry an email and a phone together, plus the signup IP, and returns one answer with a module score for each and an overall score across all of them. At signup that catches the combinations a single check misses - a fresh VOIP number, an email with no history, a datacenter IP. In KYC and AML review the country and carrier corroborate a submitted address. See fraud risk scoring for how the rules add up, and pricing for plans.

Frequently asked questions

Can a phone number lookup API tell me who owns a number?: No. The Digital Footprint phone number lookup returns facts about the number - validity, carrier, line type, VOIP class and which platforms it is registered on - never a name, address or account contents. It is not a reverse phone directory.
Which platforms can be checked by phone number?: A phone number can currently be checked on WhatsApp, Telegram, Facebook, Instagram and X (Twitter). WhatsApp and Telegram run by default, and any of the others can be named per request. Each platform is priced separately on the public rate card and billed only when it runs.
Can a phone lookup detect VOIP numbers?: Yes. The phone module returns the line type and a VOIP class that separates fixed VOIP (a business line tied to an address) from non-fixed VOIP (a number anyone can create in an app). Non-fixed VOIP is the category behind most disposable signup numbers, and it is one of the named risk signals.
Does the phone lookup return a risk score?: Yes. The phone module returns a 0-100 risk score that is the sum of the named signals that fired - for example an internet (VOIP) number - and each signal is listed with its points. Accounts can switch default rules off, change their points, or add their own rules.
Is a phone number lookup free to try?: There are free lookups to start, no card required. After that, phone intelligence and each phone platform are priced per check on the public rate card, with no subscription needed.

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