API for One-Step Unified ED Finder

Stephen P. Morse, San Francisco




This page is for website developers. It is of no use to genealogists

There are external websites that have collections of addresses for specific years. Some of these sites might like to provide links to the One-Step Unified ED Finder so that the ED Finder comes up with a secific address pre-selected. This would allow their users to obtain the desired ED with fewer key strokes. To allow for this, we have created an API (application program interface) to the One-Step Unified ED Finder. The API is as follows:
https://stevemorse.org/census/unified.html?year=<YEAR>&state=<STATE>&county=<COUNTY>&city=<CITY>&number=<NUMBER>&street=<STREET>

where
<YEAR> is the four-digit census year starting with 1880
<STATE> is the two-letter state abbreviation or the full state name
<COUNTY> is the county name
<CITY> is the city name
<NUMBER> is the house number part of the address
<STREET> is the name of the street
For example: http://stevemorse.org/census/index.html?year=1940&state=DC&city=Washington&number=1600&street=Pennsylvania Ave NW
The state will be pre-selected if it is a known state name or known state abreviation. The county will be pre-selected if it is a known county within the designated state. If the city is one of those include in the One-Step city list for the designated state, it will be pre-selected as well. If not, the "other" choice will be selected and the city name will be filled in. If the street, or some variation of it, is one of those included in the One-Step street list for that city, it will be pre-selected. And the house number will be pre-filled in as well.

There are many variations on a street name. For example, Brooklyn Avenue might be written as
Brooklyn Avenue
Brooklyn Ave
Brooklyn Ave.
Brooklyn Av
Brooklyn Av.
Similarly East 96th Street might be written as
East 96th Street
East 96th St
East 96th
East 96 St
East 96

E 96th Street
E 96th St
E 96th
E 96

E96th Street
E96th St
E96th
E96
The program will make its best effort at finding the correct street in spite of the variation of the street name used in the API. Although it will succeed most of the time, there will undoubtedly be variations that it will not recognize. For example, if the API specified Bklyn Ave, the program will probably not be able to find the correct street. In those cases, the city and state will still be correctly pre-selected, but the user will have to manually select the desired street.

An earlier version of this page gave the API for the One-Step Large-City ED Finder (as opposed to the Unified ED Finder), and only for 1940. That API is no longer supported.
© Stephen P. Morse, 2011