This calculator determines the weight (in grams per square meter) for a ream of a given basic size and grade of paper based on its basis weight in pounds (see the example below). When filling in the basis weight field, you can use either a whole number or a decimal fraction.

For a table of select standard paper weights given in both pounds and grams, see our Equivalent Weights & Grammage Conversion Chart.

Basis-Weight-to-Grammage Calculator
Basis Weight: lbs.
Select… (Or type in values below.)
Basic Size:(length × width) length
Grams per
Square Meter =


The numerical results from this calculator are estimates only and are not guaranteed by Case Paper Company as accurate in all situations.


Find the weight in grams per square meter for a ream of 25″ × 38″ Book paper that has a basis weight of 45 lbs.


 Basis Weight × 1406.5

Basic Size

= Grams per Square Meter


 45 × 1406.5

(25 × 38)

= 67 g/m2 (66.62 rounded to the nearest whole number)

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