Smarty
Zipcodestack
PostalDataPI
Geoco.io
Melissa Data Quality
Loqate
usZIPCodes.org
REST API for US ZIP, ZIP+4, and Canadian postal codes. Single unified endpoint covers address validation and standardization, radius search (centroid haversine and true spatial polygon intersection), point-to-point distance, autocomplete/typeah

Superhuman
Shortwave
Spark Mail
FiloMail
Mimestream
Leave Me Alone
Clean Email
The best and most innovative mail app to master your overloaded mailbox.
Which is more popular?
Website, pricing, platforms and company facts side by side.
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ZIP
ZIP Code API
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| Website | zip-codes.com | info.easi.net |
| Company | Startup from the United States · 2026 | — |
| Listed in |
In their own words, as submitted to SaaSHub.

API for US ZIP, ZIP+4, and Canadian postal code data. One unified endpoint set covers North America — no separate APIs by country or data type. What it does Address validation and standardization — production-grade parser with ZIP+4 append, refreshed monthly Radius search — centroid haversine and...
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