Why US paper weight is so confusing
Because "lb" refers to a ream weight at a category-specific basic sheet size rather than a fixed area, two papers can share the same pound number while one is noticeably thicker than the other. This system dates back to how paper was historically sold by ream weight before area-based metric standards existed.
When to use GSM instead of lb
Anytime you are comparing across paper categories, ordering from an international printer, or trying to judge actual thickness or stiffness, GSM is the more reliable number, since it always describes the same physical quantity regardless of what the paper is called.
Frequently Asked Questions
Is higher lb always thicker paper?
Only within the same category. A higher lb number within Bond, or within Cover, means thicker paper, but you cannot compare lb numbers across categories β 24lb Bond and 24lb Cover are very different thicknesses.
What GSM is considered "cardstock" versus regular paper?
There is no strict cutoff, but paper under about 120 GSM generally feels like regular printer or writing paper, while 200 GSM and above starts to feel like true cardstock. The 120-200 GSM range covers a middle ground often used for flyers and light covers.