Data Validation · head-to-head
US Autocomplete vs US Street Address
Smarty's US Autocomplete Pro API suggests valid, USPS-backed US addresses as a user types, turning a single free-form "search" string into a ranked list of deliverable candidates for checkout and signup forms, with optional city/state/ZIP filters to narrow the results. A separate "selected" parameter expands a chosen address into its individual secondary units (apartments, suites) when it resolves to more than one. It's part of Smarty's wider address-data platform, so one account and key also unlock the sibling US Street Address and US Extract APIs.
Smarty's US Street API is a CASS-certified single/batch address validator: it corrects, standardizes, and appends ZIP+4, county, carrier route, and delivery-point-validation (DPV) data to a US postal address, flagging vacant, undeliverable, or CMRA (commercial mail receiving agency) addresses along the way. Requests can be sent as GET query parameters or as a JSON/XML batch of up to 100 addresses per POST, and responses are returned in the same format. It shares an account and API key with Smarty's other address-data products, including US Autocomplete and US Extract.
| US Autocomplete | US Street Address | |
|---|---|---|
| Authentication | API Key | API Key |
| Pricing | freemium | freemium |
| Formats | JSON | JSON, XML |
| CORS | yes | yes |
| HTTPS | Yes | Yes |
US Street Address supports 2 response formats, while US Autocomplete offers fewer — pick US Street Address for more integration flexibility.