Signal Number Validation & Profile Lookup APIs
Signal lookup API: verify if a phone number is registered on Signal and fetch public profile data (display name, About, ACI/PNI UUIDs, avatar color, verified/blocked flags). Real-time JSON API for lead validation, identity resolution, and contact enrichment.
Signal Lookup by Phone Number
Check whether a phone number is registered on Signal and, when registered, return its public profile in one call: display name, given/family name, About bio, canonical E.164 phone, stable ACI and PNI UUIDs, avatar color, registration status, and flags (isBlocked, isSelf, showVerified, isProfileSharing). Pass the full international number (digits, with country code); the API normalizes to digits only. When the number has no Signal account, registered=false is returned.