Paper Weight & Size -- When is 80# NOT 80#?
doesn't 80# cover stock feel anything like 80# text stock?
If you feel both sheets between your thumb and index finger,
you'll find that the cover stock is stiffer and more resistant
to bending. And why doesn't a ream (500 sheets) of 8.5"
x 11" cover stock weigh the same as a ream of 8.5"
x 11" text stock?
Or, to confuse
matters further, if the Post Office requires business reply
cards (postcards) to be at least 7pt. in thickness (0.007"),
how does this measurement relate to the above-mentioned
cover weight and text weight?
First of all, 500 sheets of 80# cover
stock do actually weigh 80#, just as 500 sheets of 80# text
stock weigh 80#. The trick is that the 8.5" x 11"
cover stock noted above was cut down from a 20" x 26"
"basic size" sheet of cover stock. The basis weight
of 500 sheets of cover stock at the basic size is 80#. Text
stock is cut from a larger sheet (25" x 38").
Therefore, 500 sheets of text stock at the basic size also
What does this mean for all
the different categories of paper, and what is M weight,
To start with the simpler question, the M weight
is the weight of 1,000 sheets of a particular stock. Paper
merchants often quote the price of paper as a per-M cost
rather than a per-ream cost.
See the glossary in the next section
to better understand the more complex question of basic
sizes for different grades of paper.
Are different sizes produced beyond
these basic sizes? Yes. For example, a printer might order
a ream of 28" x 40" text stock for a particular
job (perhaps to allow for a greater number of brochures
to fit on the flat sheet with room for color bars).
How do sizes of different grades
relate to one another?
This is complex and inexact. I was once told that
55# cover was comparable to 105# text, and that 67# Vellum
Bristol was comparable to 7pt. postcard stock. And 20# bond,
or 20# laser paper, is "about" the same as 50#
text (while 24# bond, or 24# laser paper, is "about"
the same as 60# text; and 28# bond, or 28# laser paper,
is "about" the same as 70# text).
This is not a rule of thumb, since
some papers (high-bulk stock for instance) are actually
thicker, when checked with a micrometer, than the same weight
of a stock that is not high bulk. But it is a starting point
for discussion with a printer or paper merchant.
When in doubt, talk with your
printer and measure the paper's thickness with
a micrometer. Also, learn to use a paper swatch book, which
will show you the size of the parent sheets and the paper
grain direction. Even more useful than any of these metrics,
it will show you what a particular sheet feels like.
If you're printing business
reply cards, ask your paper merchant or printer
if a sheet "mics" (as in micrometer) to 7pt. This
is the legal thickness for a postcard as specified by the
US Postal Service.
If you're printing a book,
consider how the cover and text sheets will work together.
Is the cover stock too heavy or too light? If you pick an
80# cover stock to pair with an 80# text stock -- for an
annual report, for instance -- you should be fine. On the
other hand, if you're printing a 300-page paperback book,
you might want to match a 10pt. cover with 50# text. A lighter
cover might feel flimsy, while 80# text would make the thickness
of the book unwieldy, and the weight of the book might require
Choose a stock as you would
a fine fabric, by its feel between your fingers.
When in doubt, ask your printer or paper merchant to create
a paper dummy using the weight and grade you plan to spec
for the final printed product.
A BRIEF PAPER GLOSSARY
- Bond (17" x 22"): writing
papers, including ledger, that accept ink readily and
can be erased
- Coated (25" x 38"): book
paper with a clay coating ensuring smoothness (dull, satin,
- Text (25" x 38"): uncoated
book paper (often of an interesting color) used for announcements
and the like
- Offset (25" x 38"): uncoated
book paper treated with sizing to resist moisture
- Opaque (25" x 38"): uncoated
book paper treated to be less transparent
- Cover (20" x 26"): coated
and uncoated; used for book covers, brochures, etc.
- Mill Bristol (22.5" x 28.5"
and 22.5" x 35"): a board grade receptive to
folding, embossing, and stamping
- Index Bristol (25.5" x 30.5"):
an inexpensive, stiff board grade, with a harder surface
than Mill Bristol
- Tag (24" x 36"): water resistant
and foldable, used for tags
- Newsprint (24" x 36"): used
for printing newspapers; highly acidic, degrades quickly
- Digital: for copiers and ink-jet and
laser printers, as well as high-end digital presses like
Xeikon and Indigo
[Steven Waxman is a printing consultant. He teaches corporations how to save money buying printing, brokers printing services, and teaches prepress techniques. Steven has been in the printing industry for thirty-three years working as a writer, editor, print buyer, photographer, graphic designer, art director, and production manager.]