What paper weight actually tells you (and what it doesn't)
Almost every notebook lists a number in grams per square metre, and it is tempting to read it as a quality score: 120 must be better than 80. It isn't that simple.
Grams measure mass, not behaviour
Paper weight is exactly what it sounds like — how much one square metre of the sheet weighs. It says something about thickness and opacity, but very little about how ink behaves on the surface. Two papers of the same weight can behave in completely opposite ways with a wet fountain pen.
What decides feathering and bleed-through is mostly sizing — the coating or treatment that stops ink from spreading into the fibres. A thin, well-sized sheet can outperform a thick, absorbent one.
A rough guide from my own shelf
| Weight | Typical feel | Good for |
|---|---|---|
| 52 gsm | Thin, crinkly, shows ghosting | Journals you want to stay slim |
| 68–80 gsm | The everyday middle | Most pens, most notebooks |
| 90–100 gsm | Firm, little show-through | Broad nibs, highlighters |
| 120 gsm+ | Card-like, stiff pages | Light watercolour, stamps |
Ghosting is not bleeding
Ghosting is when you can see the writing from the other side; bleeding is when the ink actually passes through. Thin papers ghost, but good thin papers rarely bleed. If you write on both sides and don't mind a faint shadow, a lighter sheet gives you more pages in the same spine.
Test a new notebook on the last page, with your wettest pen, before you commit the first page to anything important.
Next time I want to write about drying times, which is where the smooth, coated papers pay a price.