LBS to GSM – U.S. to international paper weight conversion – equivalent weights & conversions
Paper stock, also called paper weight, refers to the thickness and sturdiness of paper used in printing. The weight of paper stock is determined using a scale that measures either the weight of the paper in pounds (LB) or in grams per square meter (GSM).
Cloudprinter's default measurement system for paper thickness is the metric one - GSM. However, paper stocks are measured differently in the United States compared to foreign manufacturers due to differences in measurement systems across the world.
The imperial measurement system used in the U.S. measures what is called the “basis weight” to determine the paper stock. Basis weight refers to the weight in pounds for a full ream (500 sheets) of standard-size paper. For book (text) paper, the basis size is 17” x 22”, while the standard size for cover paper is 25” x 38”. For example, a 20 lb. bond paper means that 500 sheets of this paper stock at its standard size of 17″ x 22″ weighs 20 pounds.
To convert the paper stock in pounds to grams per square meter, the following formula could be used:
1lb. of Text paper = 1.48 gsm. Multiply each pound of text paper by 1.48.
1 lb. of Cover paper = 2.708 gsm. Multiply each pound of cover paper by 2.708.
For example:
80lb. text = 118.4 gsm
80lb. cover = 216.64 gsm
Examples of paper weight conversions
Book (Text) |
Cover |
||
Basis Wt. 17” x 22” |
Grammage |
Basis Wt. 25” x 38” |
Grammage |
30 lb. |
44 gsm |
50 lb. |
135 gsm |
40 lb. |
59 gsm |
60 lb. |
163 gsm |
45 lb. |
67 gsm |
65 lb. |
176 gsm |
50 lb. |
74 gsm |
80 lb. |
216 gsm |
60 lb. |
89 gsm |
90 lb. |
243 gsm |
70 lb. |
104 gsm |
100 lb. |
271 gsm |
80 lb. |
118 gsm |
110 lb. |
298 gsm |
90 lb. |
133 gsm |
130 lb. |
352 gsm |
100 lb. |
148 gsm |
160 lb. |
433 gsm |
Use cases for different paper weights and stock options
Hereby are a few examples, of how Cloudprinter’s Print Partners from North America handle the mapping of paper stock from LB to GSM for books:
Stock requested by Cloudprinter (books) |
Stock used by Print Partner (books) |
pageblock_60off |
40# Finch Text |
pageblock_80off |
60# Williamsburg Text |
pageblock_90off |
60# Uncoated White Text |
pageblock_90off_cream |
60# Uncoated Cream Text |
pageblock_130mcg |
100# Endurance Gloss Text |
pageblock_130mcs |
100# Endurance Silk Text or 80# Matte Text |
pageblock_200mcg |
80# Sterling Gloss Cover |
pageblock_200mcs |
80# Sterling Silk Cover |
cover_250ecb |
12pt C1S Cover |
cover_130mcg |
100# Endurance Gloss Text |
If you have any questions or concerns regarding paper weight conversion - feel free to contact your Account Manager from Cloudprinter.com.