Friday, December 6, 2013

What is the Difference Between Paper Basis Weight, Caliper and Equivalent Weight for Paper Rolls?

We are often asked about the differences between paper basis weight, caliper and equivalent weight. So we thought a blog post was in order to explain the differences as it relates to paper rolls, thermal paper rolls, and wide format paper rolls

Basis Weight: The basis weight of a paper is the designated fixed weight of 500 sheets, measured in pounds, in that paper's basic sheet size. It is important to note that the "basic sheet size" is not the same for all types of paper.

Caliper: Refers to the thickness of a sheet of paper expressed in thousandths of an inch. This measurement is take with a micro meter. Normally, paper caliper should not have more than a + or - 5% variance within a sheet. Generally, the relation between caliper and basis weight- the greater the caliper (the thicker the paper) the greater the paper weight.

Equivalent Weight: While different paper types have different basic sizes, papers can still be compared by using equivalent weight.

Basis Weight ("Category") Table
Type of Paper
Basic Size – 500 Sheets
"Bond"
Ledger
Mimeo
Duplicator
Rag Paper
17" x 22"
"Offset"
Book
Text
Coated Paper
25" x 38"
"Cover"
20" x 26"
"Tag Stock"
24" x 36"
"Index"
25-1/2" x 30-1/2"