Targetlock is Postcode based location API. You can use the API to access postcode/location related API endpoints, which can get information on all postcodes in the USA using a postcode, all the locations/postcodes for a city and state, and the distance between two postcodes.
Targetlock uses an authorization token to allow access to the API for all paid tier requests. You can sign up for a new Targetlock authorization token on their pricing page.
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