When Smarty fits
US address operations that need to inspect postal and secondary-unit evidence instead of accepting a normalized string as the only result.
Check before integrating
US Street and International are different interfaces and entitlements. A returned candidate must be interpreted using its analysis fields; an empty candidate array is not an application transport error.
Provider endpoint reference
This is Smarty's documented interface. Its credentials and response format are separate from an All Them APIs account.
GET https://us-street.api.smarty.com/street-address
Authentication: Server-side auth-id and auth-token; embedded credentials have different restrictions
Inputs: street, optional street2, city/state/zipcode, candidates and auth credentials; POST supports multiple addresses
Output: Candidate array with components, metadata and postal analysis, including DPV-related fields where supplied.| Capability | What to expect |
|---|---|
| Validation approach | US postal-address candidates and analysis |
| Coverage boundary | US Street endpoint; International is a separate product |
| Decision signal | Candidate and DPV-related analysis, not a single global score |
| Apartment/unit handling | Preserve street2 and interpret secondary-address evidence |
| Workflow | Single-address GET or multi-address POST with server credentials |
| Cost driver | Address lookups, product and licensed features |
Pricing model and production access
Product-specific lookup subscriptions. Select US or International verification and the required feature/license tier. Batch requests contain multiple addresses; do not calculate price using only the number of HTTP requests.
For 10,000 address checks, include retries and customer edits, not just completed orders. Count input addresses rather than batch HTTP calls. Compare the same country mix and postal evidence; a geocoding credit and a delivery-verification check do not buy the same result.
Migration notes
Handle zero, one and multiple candidates explicitly. Preserve leading-zero ZIP codes and separate missing-unit evidence from a street match; batch IDs must map back to original input records.
Keep provider-specific authentication and response mapping inside an adapter. Preserve source timestamps and identifiers so changing a provider does not silently change the meaning of stored records.
Smarty alternatives
| Alternative | When to evaluate it |
|---|---|
| Smarty vs Google Address Validation | A checkout that needs component-level verdicts and a confirm-or-correct flow inside an existing Google Maps Platform integration. |
| Smarty vs Loqate | A multinational address-data pipeline that needs country-aware cleansing, multiple input records and explicit quality codes. |
| Smarty vs Geoapify | A location lookup or address-entry flow that can review ambiguous matches and does not require postal delivery-point confirmation. |
| Smarty vs EasyPost | A shipping workflow already using EasyPost that needs verification results before proceeding to shipment and label operations. |
| Smarty vs Shippo | A checkout or shipping system that wants explicit address-change reasons before creating labels in the same platform. |
A fair evaluation
- Use provider-approved test fixtures or addresses you have permission to process. Include international formats, accents, rural addresses and unit numbers. Do not generate arbitrary postal addresses or send private customer records without authorization.
- Define expected outcomes for known-good records and approved negative cases before the run. Keep unsupported countries and missing evidence separate from invalid addresses.
- Measure component correction, unit preservation and false rejection separately. A geocoder's building-level match is not confirmation of postal deliverability or of the person living there.
- Record whether the API suggests a correction, confirms a delivery point or merely finds a location. Require customer confirmation when a suggested change could route a parcel elsewhere.
- Count billed address checks, repeated checkout attempts, optional geocoding and batch records. Compare latency and cost per accepted decision on the same country mix. No validation result guarantees a successful future delivery.
A common integration contract
POST /api/v1/address-validation/validateReview the request contract and tell us the coverage you need. Access requires enablement; this endpoint does not execute or bill requests yet.
View endpoint and request accessSources and review dates
Documentation reviewed October 28, 2026. These are integration and plan comparisons, not measured speed or accuracy rankings. Availability, licensing and prices should be confirmed for the chosen plan.
Corrections: email faizank@docsalot.dev with an official source.