TelephoneValidate any phone number with one API call
A simple REST API that returns validity, carrier, line type, and formatting for any phone number worldwide. JSON in, JSON out, under 50ms.
No credit card required
190+
countries
<50ms
latency
99.99%
uptime SLA
10K+
req/s
Integrate in minutes
One endpoint, one API key. Works with any language or framework — no SDK needed.
curl "https://api.telephone.so/v1/validate?phone=14154582468" \
-H "Authorization: Bearer YOUR_API_KEY"Get started in 3 steps
From sign-up to production in under five minutes.
Get your API key
Sign up with Google in one click. Your API key is ready instantly — no approval process, no sales calls.
Make your first request
Send a GET request with a phone number. Get back validity, carrier, line type, and formatted numbers in under 50ms.
Ship to production
Drop it into your sign-up flow, checkout, or CRM sync. Scale from 10 to 10,000 requests per second without config changes.
Everything you need from a phone API
Validation, carrier detection, formatting, and more — all in a single request.
Simple REST API
One GET endpoint. Pass a phone number, get back a JSON response with everything you need. No SDKs required — works with any HTTP client.
Rich JSON Response
Every response includes validity, carrier name, line type (mobile/landline/VoIP), country, and three format variants: E.164, international, and national.
Carrier & Line Type
Know if a number is mobile, landline, VoIP, or toll-free before you send an SMS or make a call. Route communications the right way.
190+ Countries
Validate and format phone numbers from every major market worldwide. Handles international formats, country codes, and local numbering plans.
Sub-50ms Latency
Our edge network delivers responses in under 50 milliseconds globally. Fast enough for real-time form validation and checkout flows.
Privacy-First
Phone numbers are validated in real time and immediately discarded. Zero data retention. Fully GDPR and CCPA compliant. SOC 2 Type II certified.
API Response Examples
See exactly what you get back from the API.
{
"phone": "14154582468",
"valid": true,
"possible": true,
"format": {
"international": "+1 415 458 2468",
"national": "(415) 458-2468",
"e164": "+14154582468"
},
"country": {
"code": "US",
"calling_code": "1"
},
"type": "FIXED_LINE_OR_MOBILE",
"number": "4154582468"
}Your data never touches our servers
Phone numbers are validated in real time and immediately discarded. Zero data retention, TLS encryption on every request, fully GDPR and CCPA compliant.