Weighty matters

Understanding paper weights

When you first start working with paper, the different types, finishes and, especially, weights, can be quite confusing. More often than not, you can pick up two different brands of 60 lb. text weight paper and have them be completely different thicknesses - not to mention how much difference there is between a sheet of 60 lb. text paper and a sheet of 60 lb. cover stock!

There is a simple explanation as to why these variances occur, but first, let me give you an overview of the systems used to calculate paper weight.

Paper weights are measured in one or both of two different systems: Imperial and Metric. The Imperial system uses pounds (lbs. or sometimes just the # symbol) as the unit of measure, while the Metric system measures in grams per square metre (g/m² or gsm).

Imperial System

A paper’s weight in the Imperial system is calculated based on the weight of a ream (500 sheets for the most part, but can sometimes be 1,000 sheets) of paper in its original, uncut (base) size. Generally, for text weight, this uncut size is 25” x 38” and for bond weight (commonly used as printer paper), it is 17” x 22”. For cover (aka card) stock, the uncut size is usually 20” x 26”. The difference in uncut sizes is why a sheet of 80 lb. text weight paper will differ in thickness from a sheet of 80 lb. cover stock paper.

Because of the lack of standardization in base sizes, it can sometimes be confusing to work with the Imperial system. It is, however, the most prevalent system used in North America, so it’s a good idea to become familiar with it. If you’re ordering paper and are unsure of whether you’re going to be happy with the weight or quality, order samples. Many companies will offer sample books and swatches either for free or for a minimal charge. I always order swatches/samples myself (especially when I’m working on special projects, like wedding invitations!). It’s the only way to make sure I’m happy with the weight, look, colour, quality and feel of the paper I work with.

Metric System

The Metric system, on the other hand, is standardized. Since it deals with the weight of one square metre of the paper, it doesn’t matter what type of paper (i.e. text, cover, tissue, etc.) is being measured. Plus there’s no need to worry about what the base size of the particular paper is and how that affects the weight. As a result, it gives a more accurate indication of how thick a paper is – as long as you are familiar with the system and how heavy certain types of paper are, of course. I know many professional printers who prefer to use the Metric system for this reason.

Paper Weight Chart

This chart shows the basic conversion between the Imperial system and the Metric system. Remember that this is just a guide to give a basis for comparison - due to the variances in thickness that can happen with the Imperial system, it is impossible to have a completely standardized conversion chart.

Paper Type	Imperial Weight (lbs.)	Metric Weight (g/m2)
20 lb. Bond/Copy (most common printer paper weight)	20	75
60 lb. Text	60	89
24 lb. Bond/Copy (often sold as “premium” or “high quality” printer paper)	24	90
70 lb. Text	70	104
28 lb. Bond	28	105
32 lb. Bond	32	120
80 lb. Text	80	120
65 lb. Cover	65	175
80 lb. Cover	80	215
105 lb. Cover	105	285

I hope this post has helped answer the questions you may have had about paper weight. Have a great weekend and we’ll see you again next week!