Some people even say that the heavyweight cards are not a good as they used to be in the old days, but this is what the tradeoff is in using paper cards today and trying to be economical and also saving the environment and trees. You can find some cards with 14pt (0.014') and higher. Thick: If you are looking for really thick cards look for thickness greater than about 100lb card stock (greater than 11pt). On the other hand, if you are using them as a pack in your back pocket to take quick notes then you might prefer a thinner card. Thin: You can get thinner ones, 7pt, 0.007' but user reviews indicate that these are too thin to be used as flashcards since the paper is too thin and your answer on the back of the card shows - be careful when selecting the right index card thickness and check the thickness. 0.011' is also referred to as 100lb stock. Conversely high >350 gsm on poker size cards might feel unnaturally stiff. So, tarot or oversized cards should typically be thicker. This is because the flex is a function of both size and thickness. The larger your cards, the higher gsm you’ll typically want.
Standard: 11pt thickness (0.011') Heavyweight Oxford brand. Magic: The Gathering uses 320 gsm, Bikes & Bees playing cards are 300-310.
