Paper Weight Converter
Convert between US paper weight systems and metric gsm. Identify paper type by weight.
Convert Paper Weight
Common Paper Weight Reference
| Paper Type | gsm | Bond lb | Text lb | Cover lb |
|---|---|---|---|---|
| Tissue / Onion skin | 40–50 | 11–14 | 27–34 | — |
| Newspaper | 45–55 | 12–15 | 30–37 | — |
| Post-it / Notepad | 75 | 20 | 50 | — |
| Printer / Copy paper | 75–90 | 20–24 | 50–60 | — |
| Writing paper (quality) | 90–100 | 24–28 | 60–68 | — |
| Magazine / Brochure | 90–135 | 24–36 | 60–90 | — |
| Light cardstock | 120–160 | 32–43 | 80–106 | 65–90 |
| Cardstock (standard) | 160–250 | 43–67 | 106–166 | 90–135 |
| Heavy cardstock | 250–350 | 67–94 | 166–233 | 135–190 |
| Cardboard / Board | 300+ | 80+ | 200+ | 163+ |
Understanding Paper Weight Systems
The US paper weight system is notoriously confusing because different paper types are weighed on different base sheet sizes. A "20 lb Bond" sheet and a "50 lb Text" sheet are actually the same paper — both are about 75 gsm — just measured against different standard sheet stacks.
The metric gsm (grams per square metre) system is straightforward: it is always the weight of one square metre of the paper regardless of type. It is the most reliable way to compare papers across categories.
US Paper Weight Systems Explained
Bond/Writing (17×22" base): Used for writing paper, copier paper, letterhead. Standard office copy paper is 20 lb Bond (75 gsm) or 24 lb Bond (90 gsm).
Text/Book (25×38" base): Used for book pages, brochures, flyers. The same physical paper as Bond but the lb number is higher because the base sheet is larger.
Cover (20×26" base): Used for card covers, postcards, business cards. A "65 lb Cover" is a light cardstock.
Index (25.5×30.5" base): Used for index cards, file folders. Slightly different base size from Cover.