This example auto-fills the city and state after a zip code is entered.

Use this API to determine the distance between one zip code and multiple other zip codes. Send a GET request to /// Each zip code provided will count as a separate request. For example, if you send 5 zip codes, you will be charged for 5 requests. Any zip code not found will not be included in the response.
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Use of this API is subject to our Terms of Use. You must register your application to use the API. It’s simple and 100% free for up to 10 requests per hour. You can view our Usage Plans for information on usage above 10 requests/hr.

To prevent abuse, the API key on this page is periodically regenerated. If your request failed — with an error message indicating that the API key is not found — please reload the page and try again. We also will intentionally reject requests if our system detects abuse.

Error Codes
Status Code Reason
The request could not be understood by the server due to malformed syntax.
The server understands the content type of the request entity and the syntax of the request entity is correct but was unable to process the contained instructions.
The usage limit for your application has been exceeded for the hour time period.