The United States Postal Service and UnitedStatesZipCodes.org provide local zip code directories through their websites. Additionally, users can input a zip code and get that zip code's location.
UnitedStatesZipCodes.org allows for broader search terms. Searching for "Kings County," for instance, returns a map showing all zip codes located in Kings County, New York. The address, city and state must be entered to return a result on the United States Postal Service website as well as UnitedStatesZipCodes.org.
The United States Postal Service website also returns results for "ZIP+4." The ZIP+4 refers to a more specific location than the standard five-digit zip code, however, UnitedStatesZipCodes.org does not provide Zip+4 results.