Prelude
Prelude is a phone and email verification API - "the trust layer between your signups and your business." Its Verify API creates and checks one-time passcodes (OTP) across SMS, WhatsApp, RCS, Viber, and voice in 230+ countries, with smart multi-provider routing and built-in anti-fraud. Alongside Verify, Prelude offers Notify (transactional messaging), Lookup / Intel (phone number intelligence - line type, carrier, ported and temporary flags, CNAM), and Watch (anti-fraud risk prediction and feedback). The public REST API v2 lives at https://api.prelude.dev/v2 with Bearer API-key auth and official SDKs for Python, Node.js, Java, and Go. Prelude positions itself as a developer-first alternative to Twilio Verify.
Prelude publishes 4 APIs on the APIs.io network, including Verification API, Lookup API, Watch Anti-Fraud API, and 1 more. Tagged areas include Number Verification, Phone Verification, OTP, Authentication, and Anti-Fraud.
Prelude’s developer surface includes authentication, documentation, engineering blog, and 6 more developer resources.
API Rating
APIs
Prelude Verification API
Create or retry a one-time passcode (OTP) verification for a phone number or email address and check the submitted code. Delivery spans SMS, WhatsApp, RCS, Viber, and voice with...
Prelude Lookup API
Phone number intelligence (Intel). Look up an E.164 number to get its line type (mobile, fixed_line, voip, etc.), current and original carrier / network info (name, MCC, MNC), p...
Prelude Watch Anti-Fraud API
Anti-fraud (Watch). Predict whether a signup identifier is legitimate or suspicious using device, network, and behavioral signals, then send feedback about what actually happene...
Prelude Transactional Messaging API
Transactional messaging (Notify). Send a template-based message to a recipient over the best available channel (SMS, RCS, or WhatsApp), with variables, scheduling, expiry, deliv...
Collections
Prelude API v2
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FinOps
Prelude So Finops
FINOPSResources
Documentation 1
Reference material describing how the API behaves
Agent Surfaces 1
MCP servers, agent skills, and machine-readable catalogs
Access & Security 1
Authentication, authorization, and security posture
Operate 1
Status, limits, changes, and where to get help
Commercial 2
Pricing, plans, and the legal terms of use
Company 3
The organization behind the API