Key points
- Nib sizes are relative, not standard. A Japanese fine lays down roughly the line of a Western extra fine, and a Western medium is close to a Japanese broad.
- Finer nibs feel scratchier, put down less ink, dry faster and survive cheap paper. Broader nibs feel smoother, show ink colour and need better paper.
- A stub nib has a flat tip that makes downstrokes thick and sidestrokes thin. It flatters most handwriting and is the first special nib worth trying.
- Small handwriting wants EF or F. Average handwriting on good paper suits M. Signatures and headings suit B or a 1.1 mm stub.
Nib size is the one decision that changes how a fountain pen feels every time you pick it up, and it is the one most people make blind, because the letters on the nib do not mean what they appear to mean. A fine is not a fixed width. It is a maker’s opinion. Here is how to read those opinions and choose a width that suits your hand, your ink and your paper.
If you want the short answer: for everyday writing on mixed paper, a Western fine or a Japanese medium. For tiny handwriting or bad paper, extra fine. For signatures and the pleasure of watching ink shade, a broad or a 1.1 mm stub.
What the letters measure
The tip of a steel or gold nib ends in a small ball of hard alloy, the tipping, and the size of that ball sets the line width. Extra fine, fine, medium and broad describe that ball from small to large. Roughly, a Western extra fine lays a line around 0.4 to 0.5 mm wide, a fine 0.5 to 0.6, a medium 0.7 to 0.8, a broad 0.9 to 1.1. Those are approximations, and the next section is why.
Beyond broad come double broad, and the specialty grinds: stub, italic, oblique and architect. Those do not have a round tip at all, which is what makes them interesting.
Japanese versus Western sizing
Japanese makers grade their nibs about one step finer than European ones. The reason is practical: kanji has many strokes in a small space and needs a fine line. So a Japanese fine is close to a Western extra fine, a Japanese medium close to a Western fine, and a Japanese broad close to a Western medium.
This is the single most useful fact in this guide. If you have liked a fine from a German pen and buy a fine from a Japanese pen expecting the same line, you will get something thinner. Our comparison of the two pens most beginners choose between comes down partly to exactly this difference.
Even within a region, makers differ. One German maker’s fine is famously broad for a fine. Treat every maker’s sizing as its own scale and read what owners report about a specific pen.
How width changes the writing experience
Finer nibs put down less ink. That means faster dry times, less feathering on cheap paper, less show-through, and handwriting that stays legible at small sizes. The cost is feel: a smaller tipping ball has more contact pressure per point and more feedback, which people describe as scratchy or as pencil-like depending on temperament.
Broader nibs glide, because a bigger ball spreads over more paper. They lay down more ink, so the colour of the ink shows, shading appears where ink pools at the end of strokes, and some inks develop a metallic sheen. They need paper that can take that ink without feathering and they take longer to dry.
Medium sits between, which is why it is the default on most pens.
Stubs, italics and what they do to handwriting
A stub nib has a tip that is wide across and narrow front to back, like a tiny chisel with rounded corners. Hold the pen normally and downstrokes are wide, sidestrokes are thin. Ordinary handwriting suddenly has calligraphic weight to it. Most people who try a 1.1 mm stub keep it.
An italic is the same idea with sharp corners. The contrast between thick and thin is crisper and the nib is less forgiving: tilt your hand and the corner digs in. Italics reward a steady angle and punish a casual one.
An oblique has the flat edge cut at an angle to suit writers who rotate the pen, often left-handers. An architect grind is the reverse of a stub: thin downstrokes, wide sidestrokes, and a very distinctive look for print handwriting.
Common stub widths are 1.1, 1.5 and 1.9 mm. For writing rather than lettering, 1.1 is the useful one.
Matching nib to paper and ink
A wet ink in a broad nib on thin paper is a recipe for bleed. A dry ink in an extra fine on smooth paper can skip. The pairing matters as much as any one part.
Cheap or absorbent paper: extra fine or fine, a dry or well-behaved ink. Good fountain pen paper: anything, and a medium or broad is where that paper earns its price. Our guide to paper for fountain pens explains what to look for. Left-handed or impatient: finer nib, faster-drying ink, toothier paper.
Steel versus gold
Steel nibs are stiff and consistent. Gold nibs flex slightly under pressure, which some people love for the softness and others never notice. Gold is not smoother in itself; smoothness comes from the tipping and how well it was finished. For deciding a nib size, the material does not matter.
Who should not buy which
Extra fine is the wrong choice for anyone who found their first fountain pen scratchy or who wants to see ink colour. Broad is wrong for anyone writing in small notebooks, on cheap paper or in a hurry. Italics are wrong for a first special nib. Everyone else lands on fine or medium and is happy.
How we choose pens
When we recommend pens in our pens and ink section, each pick lists the nib sizes offered, the maker’s sizing convention, whether nibs can be swapped, and what owners report about line width and smoothness for each size. Our full process is on the how we choose page.
Final verdict
Read the maker, not just the letter: Japanese fine is Western extra fine. Choose fine or medium for everyday use, extra fine for small writing or poor paper, broad to enjoy ink, and a 1.1 mm stub as the first special nib. Then buy paper that matches.
Questions people ask
What is the difference between a stub and an italic nib?
Both have a flat, wide tip that varies line width with direction. A stub has rounded corners and forgives a sloppy angle. An italic has sharp corners, gives crisper thick-and-thin contrast, and catches on the paper if the angle wanders. Start with a stub.
Which nib size is best for a beginner?
Fine from a Western maker or medium from a Japanese one, because both give a line that behaves on ordinary paper and still shows the ink. Extra fine can feel scratchy in a cheap pen, and broad needs paper that handles wet ink.
Can I change the nib on a fountain pen?
On many entry-level pens, yes. Some makers sell nib units that pull or screw out and swap in seconds. On others the nib is fitted to the pen and swapping it is a repair job. If you want to experiment, buy a pen built for swapping.