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

Short Circuit: Your AI Assistant
iChatWithGPT
Sirius - GPT-4 Superpowers for Siri
OK Google
Saynest Lab
SmallTalk2Me
Fluently
talk to AI in voice, learn speaking second language with AI

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 | gptvoice.vercel.app |
| 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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What each product offers, as listed by its team.

Possible disadvantages
An editorial look at what each product does well and who it suits.

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Recommended for
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Your favorite AI assistant, just an iMessage away.
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The most affordable postal code API. 240+ countries, sub-5 ms responses. Simple, elegant, transparent.
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