api for zip +4 from an address

Question

What's the best api/resource to get a zip +4 from an address?

I don't want something that needs to be downloaded and updated from time to time; I want one that's updated automagically.

The goal is to look up state and federal officials without getting "duplicate" positions.

Answer 1

Yahoo has a zip + 4 in thier API, limit 5000 request per day.

Yahoo GeoCoding

Answer 2

The USPS has an API for finding/checking zip codes (among other things).

http://www.usps.com/webtools/address.htm

Answer 3

I've used Endicia at past jobs. It is a network HTTP-based API. (I can't remember if it was SOAP or REST.)

Answer 4

The USPS updates the ZIP+4 database monthly. If you examine a specific address, it seems its ZIP+4 never changes. But a significant enough pool of addresses will always have some changes every month. So, to keep ZIP+4 codes up to date, you have to reprocess your addresses periodically.

If you're going to be doing regular reprocessing anyway, then you might as well keep a copy of the USPS databases yourself and make replacing the databases a part of your reprocessing step. The big advantage is that you then have direct access to the USPS DPV, DirectDPV, LACSLink, SuiteLink, and RDI databases, which aren't available through their web API.

http://semaphorecorp.com is a cheap source of USPS databases.

I assume you're not attempting to use ZIP+4 as an address key. One ZIP+4 typically covers all addresses on one side of a street for one block, so by itself it's not suitable for keying purposes.

Answer 5

have you tried Google Maps JavaScript API V3

UPDATED:

in responce to your comment

this is easy as count 1, 2 , 3 ;)

take a look at this:

• http://maps.google.com/maps/api/geocode/json?address=Winnetka&sensor=false

you need to looking for google map geocoding service! ( Viewport Biasing )

• http://code.google.com/intl/it-IT/apis/maps/documentation/geocoding/

example code would be:

using jQuery

$(function() {
    $.getJSON("http://maps.google.com/maps/api/geocode/json?address=Winnetka&sensor=false",
    function(data) {
        var zip_code = data.results[0].long_name;
        alert(zip_code);
    });
});