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Phone validation

A phone number validator that tells you who to call.

Check that a US phone number is valid, what kind of line it is, whether it's active and whether it belongs to the person you're calling. Then get one answer: High chance, Low chance or Bad data.

Try on 250 contacts for freeRead the docs
US phone numbers onlyNo card required
Jane Doe
+1 212 555 0162
High chance
ValidYes
Line typeMobile
ActivityStrong
Name matchYes
Litigation riskNo
The problem

Valid isn't the same as reachable.

Most validators stop at "valid". A valid number can still be a landline nobody answers, a mobile that's gone quiet, or a number that now belongs to somebody else. Your reps find that out one dial at a time.

Every contact is checked against five signals and comes back with one outcome and one next step, so the list is sorted before anyone dials.

What's checked

Five checks, one answer.

CheckWhat it looks atWhy it matters
ValidWhat it looks at: Whether the number is a real, dialable US number.Why it matters: An invalid number is never worth a dial, however good the rest of the record looks.
Line typeWhat it looks at: Mobile, landline, VoIP or another kind of line.Why it matters: A person's own mobile is the line most likely to reach them directly.
ActivityWhat it looks at: Whether the line shows signs of recent use.Why it matters: A valid line that has gone quiet is less likely to be picked up.
Name matchWhat it looks at: Whether the number belongs to the name you supplied.Why it matters: A live number that belongs to somebody else is a wrong-number call.
Litigation riskWhat it looks at: Whether the number is flagged for litigation risk.Why it matters: Flagged numbers always come back as Bad data, so they stay out of the dial list.
How it works

From list to answer.

Same check, three ways in. The CSV upload, the REST API and the MCP tool run the same analysis and return the same answer. Use whichever fits how your list arrives.

  1. 1

    Send names and US numbers

    Upload a CSV, call the API with up to 100 contacts at a time, or ask your AI tool over MCP.

  2. 2

    Every contact is checked

    The five signals are read for each contact and combined into one outcome.

  3. 3

    Get one answer per contact

    High chance, Low chance or Bad data, with the next step: Phone, Multi-channel, or Email & LinkedIn.

Use cases

Where teams use it.

Clean a list before a calling session

Check the export the week you dial it, and spend the session on the people most likely to pick up.

Validate numbers as they enter your CRM

Call the API when a contact is created, so every record arrives with an outcome attached.

Check a vendor's data

Check a sample of a new data source before you buy more of it.

Example

What a checked list looks like.

A phone number validation result listing each US contact with its outcome and the action to take
An example result from checking a list of US phone numbers. Names and numbers are invented.
FAQ

Questions, answered.

Is this just a check that the number is valid?

No. Validity is one of five signals. The answer you get back is whether the contact is worth a call: High chance, Low chance or Bad data.

Which phone numbers can you validate?

US phone numbers only. Other numbers are skipped and not charged.

Am I charged for numbers you can't check?

No. Only contacts that come back with an outcome use a credit.

Keep reading

Related pages.

DevelopersA phone validation API that returns a decision.One POST with up to 100 contacts. Each comes back with a grade, a plain-language outcome and the action to take, so your code routes the contact instead of interpreting raw line data.Free toolsFree US phone number format checker.Paste a US phone number to check it's correctly formed and see it in the international format your CRM and API calls expect. Runs in your browser; nothing is sent anywhere.GuidesHow to validate phone numbers.Three levels of phone validation, from checking the format to checking the line to deciding whether a number is worth a call, with code for each.AnswerabilityWhat is an answerability score?An answerability score predicts how likely a person is to pick up when you call their number. Here's what goes into one, what comes out, and how it differs from checking that a number is valid.IndustriesReach candidates and clients on the first try.Recruiters call two very different people: candidates who aren't looking for a call and hiring managers who are busy. Check every number first, so your calls go to the right person's live phone.TemplatesCold call list cleaning template.A CSV layout and checklist for getting a calling list ready to check and dial: the columns to keep, how to format numbers, and where each contact goes once it's checked.

Know who’ll answer
before you call.

Grade 250 contacts free. No card required, and US phone numbers only.

  • US phone numbers only
  • No card required
  • One credit per checked contact
Check 250 contacts freeOr read the docs