What Does “gsm” Actually Mean?

GSM stands for grams per square metre. It is the universal standard for measuring paper weight — and more importantly, paper thickness and density. The higher the number, the heavier, thicker, and typically more opaque the sheet.

Think of it this way: if you cut a perfect one-metre square from a sheet of 70gsm paper, it would weigh exactly 70 grams. Do the same with 100gsm paper and you get 100 grams. Simple physics, profound consequences for your writing experience.

GSM affects everything from how ink absorbs into the fibres, to how a pencil’s graphite adheres to the surface, to whether you can see ghosting on the back of the page. It’s not just a number — it’s the DNA of the paper.

Understanding 70gsm Paper

70gsm is the workhorse of the paper world. It’s what fills most office printers, university notebooks, and budget composition pads. Lightweight, cost-effective, and broadly functional — but with some serious trade-offs once you move beyond a ballpoint pen.

The Strengths of 70gsm

Its lightweight nature makes it ideal for high-volume use. Notebooks made with 70gsm paper have more pages for the same thickness. If you’re a student filling hundreds of pages per semester, or a professional printing reams of documents, 70gsm makes financial and practical sense.

For standard graphite pencils (HB to 2B), 70gsm performs reasonably well. The lighter surface creates just enough tooth — micro-texture — for graphite to grip without resistance. Quick notes, sketches, and casual journaling? 70gsm does the job.

The Weaknesses of 70gsm

Here’s where 70gsm earns its bad reputation among serious writers: it cannot handle wet inks. Fountain pen ink — even so-called “dry” inks — carries significantly more moisture than ballpoint or rollerball ink. On 70gsm paper, this excess moisture has nowhere to go. It soaks into the fibres too quickly, spreads laterally, and bleeds or feathers across the page. In severe cases, wet ink will soak completely through, ruining the back of the sheet.

Ghosting — seeing the impression of your writing from the opposite side — is also common on 70gsm when used with any medium that applies pressure or ink.

Understanding 100gsm Paper

100gsm paper sits in a premium tier — substantial, smooth, and significantly more resistant to the demands of serious writing instruments. It’s the paper you’ll find in high-end journals, premium notebooks from brands like Leuchtturm1917 and Clairefontaine, and purpose-designed fountain pen pads.

The Strengths of 100gsm

The density of 100gsm paper creates a tighter fibre structure. When fountain pen ink hits the surface, it doesn’t race along the fibres chaotically — it stays put, drying cleanly along the exact line you drew. The result is crisp, sharp, beautifully defined strokes. Fine nibs look finer. Wet inks show their full shading, sheen, and shimmer without compromise.

The increased thickness also makes 100gsm far more resistant to ghosting and bleed-through. Writing on one side remains largely invisible from the other, making double-sided use genuinely practical.

For bold or extra-fine fountain pen nibs, 100gsm is virtually essential. It allows the ink to lay on the surface rather than dive into it, producing a writing experience that is noticeably smoother, more controlled, and more satisfying.

The Weaknesses of 100gsm

It costs more. Notebooks with 100gsm paper are typically 30–60% more expensive than their 70gsm counterparts. They’re also heavier and slightly thicker per page, meaning fewer pages for the same notebook dimensions.

For pencil users, 100gsm can sometimes feel too smooth. Graphite requires some surface texture to adhere effectively. On a highly calendered (polished) 100gsm sheet, lighter pencil strokes may appear faint, and the lack of tooth reduces the tactile feedback many pencil users enjoy.

Side-by-Side Comparison: 70gsm vs 100gsm

Here’s everything you need to know at a glance:

Best Paper Weight for Fountain Pens

Let’s be clear and unambiguous: if you use a fountain pen, 100gsm paper is not a luxury — it’s a necessity. The entire fountain pen experience — the smooth, flowing nib, the expressive line variation, the rich colour of quality inks — is built on the assumption of quality paper beneath it.

Fountain pens deposit ink through a gravity-fed system, meaning more ink touches the paper with each stroke compared to other writing instruments. On 70gsm paper, this abundance of ink overwhelms the loose fibre structure, leading to:

• Feathering — ink spreading along fibres like tiny ink spiders
• Bleed-through — ink seeping to the back of the page
• Inconsistent line width — your fine nib suddenly writing like a medium
• Loss of sheen and shading — the most beautiful ink properties disappear

On 100gsm paper, every one of these problems dissolves. The ink lays down cleanly, dries faster (paradoxically), and retains its full chromatic richness. For inks with shimmer particles or sheen properties, the difference between 70gsm and 100gsm is the difference between seeing the magic and not seeing it at all.

Recommended GSM for Different Fountain Pen Situations

For everyday journaling and note-taking with a fountain pen: 90–100gsm is the sweet spot. For calligraphy and art projects where ink pooling is intentional: 100–120gsm. For casual sketching with a light flex nib: 80gsm can suffice if the paper has a smooth finish.

When shopping for notebooks, look for terms like “fountain pen friendly,” “ink resistant,” or brands known for premium paper. Clairefontaine’s 90gsm and Tomoe River’s 52gsm (a special case due to its unique coating) are fan favourites precisely because weight alone doesn’t tell the whole story — coating and sizing matter too.

Best Paper Weight for Pencils

Pencils are a different story entirely. Unlike fountain pens, which deposit liquid, pencils leave behind solid graphite particles that sit on — or within — the paper’s surface texture. This means the relationship between pencil and paper is primarily about tooth, not absorption.

Why 70gsm Often Works Well for Pencils

Standard 70gsm office or notebook paper typically has a slightly textured surface — enough microscopic roughness to catch graphite particles and hold them in place. For HB pencils (the everyday writer), 2B pencils (richer, darker marks), and general sketching, 70gsm provides a responsive, tactile surface that most pencil users find satisfying.

The lightweight nature also means pencil lines erase cleanly without ghosting, though heavy erasure can damage or pill the thinner fibres.

When 100gsm Is Better for Pencils

For soft pencils (4B and above), heavier paper wins. Soft pencils deposit more graphite per stroke. On thin 70gsm paper, the graphite can smear easily and even puncture the page if pressure is applied. 100gsm offers a more resilient surface.

For artists using pencils, 100gsm textured paper (look for “cold press” or “laid” finishes) provides a surface that creates beautiful tonal gradients, supports layering, and withstands repeated erasure — critical for detailed artwork.

Mechanical pencil users may also prefer 100gsm, as the fine, rigid lead of mechanical pencils can scratch or tear thinner paper, especially when drawing circles or applying lateral pressure.

The Verdict: Which Should You Buy?

The answer depends on your primary writing instrument — but there’s a clear winner for most serious writers.

If you’re building a stationery collection or buying a single notebook to serve multiple purposes, 100gsm is the versatile, future-proof choice. It costs a little more, but it handles every writing instrument better than its lighter counterpart — and it elevates your daily writing from functional to genuinely enjoyable.

Life is too short for paper that fights your pen. Choose wisely, and every page becomes a pleasure.

Frequently Asked Questions