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Quickly standardize a postal address using MelissaData or USPS - Fork that includes Apartment Numbers and Units
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A tiny Ruby library to quickly standardize a postal address, either through MelissaData or Google Maps.


If you are using Rails, put this in your environment.rb:

config.gem 'address_standardization'

Then run rake gems:install to install the gem.

Otherwise, just run

gem install address_standardization


Right now this library supports two services: MelissaData and Google Maps.

MelissaData provides two services itself: US address lookup and Canadian address lookup. They both work the same way, however. First, here's how to standardize a US address:

addr = AddressStandardization::MelissaData.standardize_address(
  :street => "1 Infinite Loop",
  :city => "Cupertino",
  :state => "CA"

This submits the address to MelissaData. If the address can't be found, you'll get back nil. But if the address can be found (as in this case), you'll get an instance of AddressStandardization::Address. If you store the instance, you can refer to the individual fields like so:

addr.street  #=> "1 INFINITE LOOP"    #=> "CUPERTINO"
addr.state   #=> "CA"     #=> "95014-2083" #=> "USA"

And standardizing a Canadian address:

addr = AddressStandardization::MelissaData.standardize_address(
  :street => "103 Metig St",
  :city => "Sault Ste Marie",
  :province => "ON",
  :country => "Canada"
addr.street      #=> "103 METIG ST RR 4"        #=> "SAULT STE MARIE"
addr.province    #=> "ON"
addr.postalcode  #=> "P6A 5K9"     #=> "CANADA"

Note that when standardizing a Canadian address, the :country must be "Canada" (or "CANADA", or anything like that). Otherwise it will be treated as a US address.

Also note that I'm referring to the address's province as province, but you can also use state if you like. Same goes for the postal code -- you can also refer to it as zip.

Using Google Maps to validate an address is just as easy:

addr = AddressStandardization::GoogleMaps.standardize_address(
  :street => "1600 Amphitheatre Parkway",
  :city => "Mountain View",
  :state => "CA"
addr.street     #=> "1600 AMPHITHEATRE PKWY"       #=> "MOUNTAIN VIEW"
addr.state      #=> "CA"        #=> "94043"    #=> "USA"

And, again, a Canadian address:

addr = AddressStandardization::GoogleMaps.standardize_address(
  :street => "1770 Stenson Blvd.",
  :city => "Peterborough",
  :province => "ON"
addr.street      #=> "1770 STENSON BLVD"        #=> "PETERBOROUGH"
addr.province    #=> "ON"
addr.postalcode  #=> "K9K"     #=> "CANADA"

Sharp eyes will notice that the Google Maps API doesn't return the full postal code for Canadian addresses. If you know why this is please let me know (my email address is below).


If you find any bugs with this plugin, feel free to:


(c) 2008-2010 Elliot Winkler. Released under the MIT license.

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