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Using the Library of Congress Classification System in the Main Library: Learn More About Call Numbers

This guide is a tutorial for using the LOC Classification System in the Anderson Academic Commons.

LOC Classification Outline

The LOC Classification Outline is available on the Library of Congress' website.

Hardcopies are available at the Research Center Desk.

Interpet the Call Number

1. The first letter is the class. Any additional letters are the item's subclass. The classes are arranged alphabetically in the stacks, with the subclasses are arranged alphabetically within the alphabatized classes.


2. The next portion of the call number is a one to four digit number. A call number with a smaller number is shelved before one that has a larger number. Some of these numbers may be divided by a decimal: these are also read numerically (smaller numbers are shelved before larger numbers). The books categorized in this subject will all be shelved within this range.


3. The final information needed is the series of letters and numbers that follow the decimal point. Sometimes there are two letter and number combinations that follow a decimal. The first grouping, in these cases, is related to the subject of the work. The second grouping is related to the author. Use these shelving rules to quickly find the call number you are looking for:

  1. The letter following the decimal is shelved alphabetically. Cutter numbers beginning with .B are shelved before those starting with .C
  2. The digits that follow the letter are shelved in ascending order. For example, items beginning with .C3 will be shelved before items with .C4. Likewise for subsequent digits: .C34 will be shelved before .C35
  3. Items with only one digit after the letter are shelved before items with multiple digits. For example, .C3 is shelved before .C34, which is in turn shelved before .C345 (but each of these examples will be shelved before .C4)

4. Finally, within parenthesis is the year of publication.



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