The University of Illinois Library does not have publicly available online resources for cataloging. However, members of the public needing call numbers for individual titles, and without access to more specialized cataloging materials, may find the below resources useful. Those needing a description of the resources necessary to create full catalog records beyond creation of call numbers should review the ALA Library's Fact Sheet "How to Acquire Cataloging Tools."
Members of the public who live near the University may consult some print cataloging resources in person at the Social Sciences, Health, and Education Library's non-circulating reference collection. These resources include class schedules for Dewey and Library of Congress classification, Library of Congress Subject Headings, and some other more specialized classification schemes or subject headings lists. As of 2013, the Library of Congress also makes its Subject Headings manual and Classification Schedules available freely online, under "Products Available for Download" at their website.
This website from the Internet Public Library describes the structure of Dewey and Library of Congress call numbers, with links to a variety of useful resources.
Most questions about call numbers involve the initial class number used to place the book according to subject. You can use these resources to find class numbers for individual titles. However, rare items may not be found in any available tool.
You can search OCLC Classify by title, author, or ISBN. The entry for each book will tell you the most common Dewey and Library of Congress class number used by libraries for that book, and sometimes class numbers for other classification systems. It will also show alternate numbers used by libraries. However, you should be aware that a class number is usually only the first part of a call number, and you may need to consult other sources on constructing the full number. This resource is less likely to work for rare items.
An alternate way to find complete call numbers for books is to search WorldCat, a collective catalog for libraries worldwide, for the title and select a library that is listed as an owner to see what number has been assigned in the library’s catalog. You are more likely to find Library of Congress call numbers this way. One weakness of this method is that it may be hard to judge whether the library is using an unusual call number for that book, versus the "big picture" you can get from OCLC Classify.
This site offers the ability to drill down into the Dewey schedules, which you could use to explore possible class numbers. It does not offer a complete listing of all numbers, and different parts of the classification scheme have different levels of specificity.
If you have not already done so, you might want to start your research at your local library, which may have cataloging guides or an interlibrary loan service you can use to obtain them. Useful texts include:
For more online cataloging resources, see our list of web resources.