Answered By: Sally Bryant
Last Updated: Apr 07, 2015     Views: 9

How to Read Library of Congress Call Numbers

 

Each book, video, DVD and CD has a unique call number. Think of the call number as an address that tells you where an item is in the library.

     Call numbers can begin with one to three letters which indicate the item's broad subject area.

Example:

H=Social Sciences
N=Art
Q=Science

      The subsequent lines consist of numbers and a combination of letters and numbers. 

The first line should be read alphabetically.

Q

QA

QH

The second line should be read numerically.

LB
5

LB
41

LB
1507

 

The third line should be read alphabetically first, then the number should be read as a decimal.

BF
891
.B833

BF
891
.B84

BF
891
.S548

Sometimes a call number will have a fourth line. If that line is alphanumeric like the third line, read it the same way.

TK
5105.875
.I57
I557

TK
5105.875
.I57
I568

TK
5105.875
.I57
I58

     Any additional lines that indicate a date, volume number, copy number, or other annotations should be read logically. If it is a year, read it chronologically. If it is a volume number, read it numerically, etc.