Geocoding · head-to-head
GeoJS vs Postcodes.io
GeoJS is a free, no-signup IP geolocation lookup that returns country, city, ASN, and timezone data as JSON or JSONP over HTTPS with open CORS. It's built for simple client-side and ChatOps integrations rather than high-volume commercial traffic, and has no paid tier.
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.
| GeoJS | Postcodes.io | |
|---|---|---|
| Authentication | None | None |
| Pricing | free | free |
| Formats | JSON, JSONP | JSON |
| CORS | yes | yes |
| HTTPS | Yes | Yes |
GeoJS supports 2 response formats, while Postcodes.io offers fewer — pick GeoJS for more integration flexibility.