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How to Read Call Numbers

Call numbers are how we locate a book on the shelves.

It's essentially a book's GPS coordinates within the library. Call numbers are usually found on the spine of a book. If the spine is narrow, look on the cover on the left side.

In the catalog, look for a message like the one below that says "Available at Jamestown - Raugust Library" followed by a string of numbers and letters.

"Available at Jamestown Raugust Library" message in the catalog

The string of numbers and letters? That's the book's call number!

call number blown up on book spineHere's how to find a book by its call number.

TIP: When you're looking for a book on the shelf, it helps to jot down or have the title of the book handy.


1. Read the digits before the decimal point as a whole number.

For this example - 808.51 F843s - head upstairs and look for the 800s. Browse a shelf until you find books with call numbers that start with the number 808.

TIP: Look at the cards at the end of each set of shelves (near the top) to know what call numbers are in that section.


2. When you've found the general area of the first number, take a look at the numbers after the period.

Read these as a decimal. So, .5 comes before .51, but so does .505.

Why? Because

.5 = .500
.505 = .505
.51 = .510


3. When you've narrowed in on the decimal, take a look at the rest of the call number.

Read the letter alphabetically, and the numbers after it as another decimal. At this point, you can also start browsing for the title of the book you're looking for.


Books are organized by subject, so browse around your book, too.

Take a look at what's next to the book you're looking for on the shelf. Since we organize by subject, you may find other useful books nearby!


Can't find your book?

Make sure you're looking in the right collection. If you see the words General Collection before the call number, head upstairs. If you see E Curr Fiction, Curr Fiction, or Curr Non-Fiction, head to the Curriculum Library on the main floor of the library. The Curriculum Library is color-coded. E Curr Fiction books have orange stickers along their spines, Curr Fiction books have blue stickers, and Curr Non-Fiction books have green stickers.

If you still can't find it, come by the Information Desk and we'll try to track it down.