Lob.com vs US Extract

Lob's US Address Verification API checks, standardizes, and CASS-certifies a US postal address in real time, returning delivery-point-validation flags, vacancy and building-type metadata, and a corrected/deliverable address in one JSON response. It's the same verification engine behind Lob's broader direct-mail automation platform (mail creation, printing, and USPS tracking), so a key created for one Lob product works across the rest. Authentication is a single API key sent as the HTTP Basic Auth username, with separate test and live keys so integrations can be built and tested before any usage is billed.

Smarty's US Extract API scans arbitrary blocks of text — emails, PDFs-turned-text, scraped web pages, free-text form fields — to locate and validate US postal addresses embedded inside them, rather than requiring the caller to already know where an address starts and ends. Each match comes back with the same standardized, USPS-checked components (city, state, ZIP+4, delivery-point data) as Smarty's dedicated street-address API, plus the surrounding text offsets. It shares billing and account access with the rest of Smarty's address-data platform, so an existing Smarty key also works here.