Geocoding · head-to-head
Postcodes.io vs ViaCep
Postcodes.io is a free, open-source (MIT-licensed) UK postcode lookup and geocoding API: it validates postcodes, reverse-geocodes coordinates to the nearest postcode, and returns administrative geography — ward, constituency, parish, LSOA/MSOA, and more — sourced from the ONS Postcode Directory. It's built and maintained by Ideal Postcodes as a free public service, with a paid Ideal Postcodes product available for teams needing rooftop-level precision or fresher data.
ViaCEP is a free, high-availability web service for looking up Brazilian postal codes (CEP): given an 8-digit CEP it returns street, neighborhood, city, state, and IBGE/DDD codes, with a reverse address-to-CEP search available too. It's run by WBX and widely embedded across Brazilian dev tooling — its own docs warn that heavy bulk-validation traffic against it can trigger an automatic, indefinite IP block.
| Postcodes.io | ViaCep | |
|---|---|---|
| Authentication | None | None |
| Pricing | free | free |
| Formats | JSON | JSON, XML |
| CORS | yes | yes |
| HTTPS | Yes | Yes |
ViaCep supports 2 response formats, while Postcodes.io offers fewer — pick ViaCep for more integration flexibility.