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
Decidim
Polis
True Causes is a tool for group root-cause analysis at scale: participants independently propose and link causes, building one shared causal map whose high-leverage roots identify what to act on. It digitizes and scales Structured Democratic Dialogue
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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TC
True Causes
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|---|---|---|
| Website | zip-codes.com | truecauses.org |
| Pricing | — | |
| 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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