Know if anumber is validbefore you call
Validate phone numbers instantly and identify validity, line type, carrier and country before your team calls them.
Try any number
Before validation
After validation
Valid
- Line type
- Mobile
- Carrier
- T-Mobile
- Country
- United States
The problem
Bad phone data wastes good dials.
Every disconnected, reassigned or mistyped number costs a caller another attempt that was never going to connect. The list looks full. The dialling day says otherwise.
Data ≠ reality
A number in the CRM is not a number that works
It was accurate when somebody typed it in. Nothing about sitting in a database keeps it that way.
The wasted dial
The dial is the only test most teams run
Which means the discovery that a number is dead costs a caller their time rather than a lookup.
Bad data travels
Bad records spread
Exported, enriched, merged and re-imported, an unusable number travels through every system it touches.
Why it happens
Phone data doesn't stay accurate forever.
Nothing you do to a spreadsheet keeps the lines behind it connected. Three things quietly break a list between the day it was built and the day it is called.
Numbers get disconnected
People change jobs and providers. A number that worked last quarter may be disconnected today, while the record in your CRM stays the same.
Line types and carriers change
Numbers get ported between networks and move between mobile and fixed. The number you hold stays the same while the carrier behind it changes.
Lists go stale across sources
A record assembled from a provider, a form fill and a CRM export inherits the age of all three. The oldest part decides how good it is.
Your stored record
+1 212 555 0184
- JanActiveCarrier A
Record added to your CRM.
- AprPortedCarrier B
Number ported to a new network.
Your CRM record unchanged.
- AugDisconnectedNo carrier
Number now disconnected.
Your CRM record unchanged.
Reality changed.
Your stored record didn't.
Outdated data leads to wasted dials, lower connect rates and lost opportunities.
The solution
Check every number before you call.
Validate one number, upload a list, or send it through the API.
Every validation returns the same core data.
Before validation
Phone number
+1 212 555 0184
- Validity
- Unknown
- Line type
- Unknown
- Carrier
- Unknown
- Country
- Unknown
After validation
Valid
- Line type
- Mobile
- Carrier
- Verizon
- Country
- United States
- International format
- +1 212 555 0184
Works the same whether you validate through:
Checker
One number
CSV
Upload a list
REST API
Your stack
MCP
AI agents
Coverage
Built for phone data at global scale.
Numbers in full international format are read as they are. Numbers in a local format are checked against a country you choose, so a list from several markets needs no normalising first.
- 200+
- Countries & territories
- 18,000+
- Carriers covered
- 1B+
- Numbers tracked
API & MCP
Use Will This Person Answer from your stack or AI agent.
The same validation, API key and credit balance across REST and MCP.
Validate a phone number from your app or backend.
Request
curl -X POST https://app.willthispersonanswer.com/api/v1/validate \-H "Authorization: Bearer YOUR_API_KEY" \-H "Content-Type: application/json" \-d '{"phone_number":"+12125550184"}'Response
200 OK{"valid": true,"phone_number": "+12125550184","line_type": "Mobile","carrier": "Verizon","country": "United States","country_code": "US","country_calling_code": "1","is_prepaid": null}Start validating in minutes.
One API key for REST and MCP.
Pricing
Pay only forwhat you validate.
No subscription. Credits never expire.
The more you validate, the lower your rate.
100 validations
$30
$0.30 each
1,000 validations
$200
$0.20 each
10,000 validations
$1,500
$0.15 eachBest rate
- 1 credit = 1 validation
- Credits work across CSV, API & MCP
Questions, answered.
Everything you need to know before validating your first list.
One credit validates one phone number, whichever way you send it. In a CSV, blank cells are skipped and the same number appearing twice is only counted once, so you are charged for unique numbers rather than rows.
Validate a single number from the checker, upload a CSV for bulk validation, use the REST API, or connect an MCP-compatible AI tool. CSV, API and MCP validations use the same Will This Person Answer credits. The checker also includes one free check with no account.
Yes. Upload a CSV up to 5 MB and choose which column holds the phone numbers. A single file can contain up to 10,000 numbers to validate.
Validation covers more than 200 countries and territories. Numbers written in full international format are read as they are; numbers in a local format can be checked against a country you choose.
For each number: whether it is valid, the line type, the carrier it was allocated to, and country details including the country code and dialling code. In a bulk file that arrives as 9 new columns added to your original rows.
No. Validation tells you whether a phone number is real and in use, and returns technical information about it. Whether anybody picks up is a different question and this product does not claim to answer it.
Yes, both are live. The REST API validates one number per request from your own code, and the MCP endpoint gives a compatible AI agent the same validate_phone tool. Both authenticate with one API key you create in your account.
Stop dialling numbers that don't work.
Start validating your phone data.