Genealogical Research: Using the IPUMS

To Interested Genealogists:

You are welcome to work with the IPUMS data, but you should be aware of its severe limitations for genealogical purposes. Only the 1850-1880 and 1920 samples contain names of individuals. Moreover, the largest of these files are 1-in-100 samples of the population, meaning there is a 1 percent chance of finding any particular person in the data.

The data extraction system is not suited for genealogical research. The system is not a search engine. You cannot search for any particular name in the data, and the system will not select out cases on the basis of name.

If you wish to try your luck with the data, you should also be aware, if you are not already, that the data is "raw" (i.e., it is just strings of numbers with names and addresses embedded). Each line represents an individual or household. The IPUMS codebook is required to interpret the numbers. Most software - especially word processors - is unable to handle files as large as these. SPSS or SAS are the most frequently used programs to deal with the data.

Data for the complete 1880 census are available on two web sites which contain programs to search the data by name ( and These sites also help genealogists search other historical census databases and are far better suited to genealogical research than the IPUMS is.