Paper weight
45 gsm paper
45 gsm paper equals 12 lb bond, 30.4 lb text or 16.6 lb cover. Typical uses: newsprint, paperback novels, directories. Lightweight and inexpensive; often groundwood with lower brightness.
12 lbbond / writing
30.4 lbtext / book
16.6 lbcover
≈ 56 µmthickness (uncoated)
Equivalent US basis weights
| Grade | Pounds | Basic sheet |
|---|---|---|
| Bond / Writing | 12 lb | 17 x 22 in |
| Text / Book / Offset | 30.4 lb | 25 x 38 in |
| Cover | 16.6 lb | 20 x 26 in |
| Index | 24.9 lb | 25.5 x 30.5 in |
| Bristol | 20.5 lb | 22.5 x 28.5 in |
| Newsprint / Tag | 27.7 lb | 24 x 36 in |
Estimated thickness and pages per inch
| Paper type | Caliper | Points (mil) | Pages per inch | Spine for 300 pp |
|---|---|---|---|---|
| Uncoated offset | 56 µm | 2.2 pt | 903 PPI | 0.332 in |
| Bulky book paper | 68 µm | 2.7 pt | 753 PPI | 0.399 in |
| Coated (gloss/silk) | 40 µm | 1.6 pt | 1,254 PPI | 0.239 in |
Caliper ≈ grammage × bulk. Ask your printer for the measured caliper of the actual stock.
Sheet and ream weights
| Sheet | One sheet | Ream (500 sheets) |
|---|---|---|
| A4 | 2.81 g | 1.4 kg |
| US Letter | 2.71 g | 3 lb |
What it is used for
Newsprint, paperback novels, directories. Lightweight and inexpensive; often groundwood with lower brightness.