Postcodes.io
LiveLast verified 24 Sept 2026
Validates and geocodes UK postcodes, returning administrative, electoral and census-area data.
Example request
curl -s 'https://api.postcodes.io/postcodes/SW1A2AA'
Free tier, in plain English
Fully free and keyless with no published rate limit; the project is open-source and can also be self-hosted.
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