Build secure experiences using data with Lookup API
Lookup API transforms your phone intelligence data into trusted interactions. Build onboarding and engagement experiences that improve delivery and mitigate risk seamlessly without user input.

Verify, secure, and optimize engagement
with one integrated API
Lookup API adds a seamless layer of security to customer relationships using real-time phone data. Improve conversion and delivery rates, spot risk, and halt fraud. Then integrate with Twilio Verify, Programmable Messaging, and more to enhance your engagement solution with best-in-class security.
Benefits
Improve security, conversions,
and delivery at once
Use cases
Put up-to-date phone
intelligence to work at scale
Improve message deliverability
Delivery errors frustrate users who expect real-time communications. Improve contact rates by validating a number before you send. Distinguish mobile numbers from landlines, format numbers correctly, and optimize SMS routing with carrier data for optimal delivery.
Personalize messaging and voice calls
Personalization is key to a quality customer experience. Identify inbound callers globally by determining the name associated with phone number to personalize engagement over SMS and voice calls, and enhance your marketing at any scale.
Enrich data and risk models
Businesses use customer data to enrich user profiles and understand risk. Access real-time user signals like phone line type, SIM tenure, connectivity status, carrier, and more to improve risk models, scrub contact lists, and make more accurate business decisions.
Mitigate fake accounts and takeovers
Stopping SIM swap fraud, fake account creation, account takeovers, and promo abuse is a business priority. Halt takeovers when you identify risk signals of compromised numbers. Mitigate fakery with Line Type Intelligence that spots suspicious virtual numbers.
Features
Build trusted relationships
upon real-time insights

“We’ve never had a reliability issue with Twilio, and I think that speaks to the nature of its scalability and reflects on every single product we’ve worked with Twilio on so far.”
Pricing
Enhance your engagement solution
with seamless security in one API
Sign up for Twilio free to start building without commitments. Only pay for what you use with flexible pay-as-you-go pricing.