Callook.info
FreeLiveLast verified 24 Sept 2026
Looks up US amateur radio callsigns against current FCC license data, with license and address details.
Example request
curl -s 'https://callook.info/w1aw/json'
Free tier, in plain English
No API key, sign-up or published rate limit; the API reference says it is free to use however you wish.
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