140 lb index paper
253 g/m²
140 lb index · basis size 25.5 × 30.5 in · Index cards, tabbed dividers and stiff record cards.
Where 253 gsm comes from
An American basis weight is the weight of 500 sheets at that grade's basis size. For index that size is 25.5 × 30.5 inches, so:
500 sheets × 25.5 × 30.5 in = 388,875 in² = 250.9 m²
140 lb = 63,503 g
63,503 g ÷ 250.9 m² = 253 g/m²The same number, a different paper
140 lb is not one weight. Because every grade is weighed at its own sheet size, the same pound figure describes papers that are nothing alike:
| Grade | Basis size | 140 lb is | vs index |
|---|---|---|---|
| Index | 25.5 × 30.5 in | 253 gsm | — |
| Bond / Writing | 17 × 22 in | 526 gsm | 2.08× |
| Text / Book | 25 × 38 in | 207 gsm | 0.82× |
| Cover | 20 × 26 in | 379 gsm | 1.50× |
| Tag | 24 × 36 in | 228 gsm | 0.90× |
| Bristol | 22.5 × 28.5 in | 307 gsm | 1.21× |
This is the reason to ask for gsm. One number, no grade, no ambiguity — 253 gsm is 253 gsm whoever is printing it.
Frequently asked questions
What is 140 lb index paper in gsm?
253 gsm. 140 lb means 500 sheets at the index basis size of 25.5 × 30.5 inches weigh 140 pounds.
Is 140 lb index the same as 140 lb bond?
No, and the difference is large. 140 lb index is 253 gsm; 140 lb bond is 526 gsm — 2.08 times as heavy. The pound number is the weight of 500 sheets at a size that differs by grade, so it cannot be compared across them.
What is 140 lb index used for?
Index cards, tabbed dividers and stiff record cards. At 253 gsm: board rather than paper, needing a press with a straight paper path.