Phone Validation API

Validate phone numbers, determine carrier name, line type, and prepaid status, and identify disconnected phone numbers with a phone activity score.

  • id: "Phone.3dbb6fef-a2df-4b08-cfe3-bc7128b6f5b4",
  • phone_number: "2069735100",
  • is_valid: true,
  • activity_score: 57,
  • country_calling_code: "1",
  • country_code: "US",
  • country_name: "United States",
  • line_type: "NonFixedVOIP",
  • carrier: "Level 3 Communications, LLC",
  • is_prepaid: false

The number lookup app has reached its limit for the day

Please come back later or contact us for a demo or free trial

Try any phone number

Looking for inspiration? Give these a try:

Is Valid

Analyzes the number syntax and whether it is a valid US or CA number.

is_valid: Ready...

Activity Score

Indicates whether the phone is connected or disconnected, and returns a 1–100 rating for phone activity volume.

activity_score: Ready...

Line Type

Identifies line type of the phone behind the number.

line_type: Ready...


Identifies the carrier of the phone line behind the number.

carrier: Ready...


Identifies the country code and country name associated with the number.

country_name: Ready...

Is Prepaid

Indicates whether the number is a prepaid line.

is_prepaid: Ready...

Phone Validator API Use Cases


Phone Activity Score

Indicates if a phone is connected or disconnected. 

Validity Checks

Shows whether a number is valid, assigned to a carrier, and is in-service.


Identifies all U.S.-based carriers, including MVNOs.

Line Type

Provides seven unique line types, including mobile, fixed and non-fixed VoIP, landline, premium, toll-free, and voicemail service.

Prepaid Status

Indicates whether a mobile number is part of a prepaid plan.

Built by Developers, for Developers

Built for Speed

Built for Scale

Built for Reliability

World-Class API Documentation & SDKs

Customer-Obsessed Technical Support


Phone Numbers Tracked


QPS (up to)




Trestle’s Phone Validation API provides several benefits that can be valuable for businesses and organizations. Here are some of the key advantages of our phone validation tool:

Improved Conversion Rates

Weeding out junk leads with invalid, temporary, or disconnected numbers with Phone Validation API ensures sales teams can focus on the best leads and improve conversions.

Improved Data Quality

Ensure that the phone numbers collected or stored in your systems are valid and connected. By validating phone numbers in real-time, you can detect and eliminate incorrect, disconnected, or fake numbers from your lead lists and CRM systems.

Improved Message Deliverability

Boost your delivery rates and cut unnecessary costs with Phone Validation API. Distinguish mobile numbers from landlines and VOIPs and optimize SMS routing with carrier data for optimal delivery, ensuring your messages reach the right audience.

Reduce Fraud and Fake Accounts

Protect against fraud with authoritative phone intelligence data. Phone Validation API uses real-time risk signals to detect fraud and trigger step-up authentication when needed.

Enhanced Customer Experience

Phone Validation API provides a better experience with passive authentication for legitimate users using phone metadata intelligence, while step-up authentication is only triggered when needed for suspicious sign-ups.

Phone Validation API Pricing




1,000 queries per month

Small Business



5,000 queries per month


Custom Pricing

Uncapped queries


Making APIs easily accessible, coding experience or not.

Get your free
Phone Validation API key today