What is an Address Verification API?

An address validation API is a RESTful web service that validates, standardizes, parses, geocodes, and provides a lot more metadata about an actual, real-world address adhering to local postal standards. It uses GET and POST request methods to return responses in JavaScript Object Notation (JSON) or Extensible Markup Language (XML).

While traditional verification services require users to upload photocopies of documents like utility bills or lease agreements, this method can be time-consuming and costly for both businesses and their customers. Address validation eliminates this step, providing a seamless user experience with fewer data entry errors during account creation or checkout, and enabling companies to verify addresses instantly.

Using reference data from various sources around the world, the address validation API analyzes and compares an inputted address to its known database to output a standardized address. This includes reordering components of address, replacing common roadway identifiers (like street and parkway) with their official abbreviations, removing duplicate elements in an address, and correcting typos.

If the addressed location is a business, a business classification is assigned. If it is a residence, a residential classification is assigned. If it is a mix, it is classified as a mixed address.

Some services will also provide additional data, like a full carrier route code for US-based addresses or country-specific formatted postcodes for other countries. This can help businesses with their KYC processes or their Trust & Safety initiatives by adding an identification signal to verified addresses.