Fountain Pen Nib Widths vs. Lead Hardness Scale
Comparing 2 standards across 14 specifications. 14 key differences identified.
Fountain Pen Nib Widths are standardized tip grinding grades that determine ink line width, categorized from Extra Fine (EF) to Double Broad (BB) and Calligraphic Stubs (1.1 mm to 1.5 mm). Crucially, Japanese nibs (Pilot, Sailor, Platinum) write approximately one full step finer than Western nibs (Pelikan, Lamy, Kaweco) due to the dense stroke requirements of East Asian kanji characters.
The Graphite Hardness Grading Scale (standardized under ISO 15184 and ASTM D3363) classifies pencil graphite from 9H (hardest, lightest grey, highest clay content) through HB (medium equilibrium) to 9B (softest, darkest black, highest graphite content). HB is the universal writing standard and the exact equivalent to the North American No. 2 pencil.
Specification Comparison Table
14 Parameters| Parameter / Spec | ||
|---|---|---|
|
Extra Fine (EF)–Japanese
|
Approx. 0.20 to 0.28 mm line width (hairline precision) | — |
|
Extra Fine (EF)–Western
|
Approx. 0.35 to 0.40 mm line width (similar to Japanese Fine) | — |
|
Fine (F)–Japanese
|
Approx. 0.30 to 0.38 mm line width (standard everyday Japanese notebook writing) | — |
|
Fine (F)–Western
|
Approx. 0.50 to 0.60 mm line width (similar to Japanese Medium) | — |
|
Medium (M)–Japanese
|
Approx. 0.50 to 0.58 mm line width | — |
|
Medium (M)–Western
|
Approx. 0.70 to 0.80 mm line width (plentiful wet ink flow) | — |
|
Broad (B) & Stub (1.1 / 1.5 mm)
|
Broad: 0.9–1.0 mm | Stub: Flat rectangular tip with thick downstrokes and hairline cross-strokes | — |
|
Tipping Material
|
Sintered osmium/iridium/ruthenium platinum-group alloy sphere welded to gold or steel tines | — |
|
Hard Grade Range (9H to 2H)
|
— | 9H, 8H, 7H, 6H, 5H, 4H, 3H, 2H — high clay/polymer binder ratio, crisp hairline precision, zero smudging |
|
Medium Equilibrium Range (H, F, HB, B)
|
— | H (Hard), F (Fine point retention), HB (Hard Black — standard writing balance), B (Black) |
|
Soft Grade Range (2B to 9B)
|
— | 2B, 3B, 4B, 5B, 6B, 7B, 8B, 9B — high graphite content, deep velvety blacks, artistic shading |
|
US No. 2 Pencil Equivalent
|
— | HB grade (mandatory for optical Scantron standardized bubble test optical scanners) |
|
US Numbering System Cross-Check
|
— | #1 = B | #2 = HB | #2.5 = F | #3 = H | #4 = 2H |
|
Origin
|
— | Developed by Joseph Hardtmuth of Koh-i-Noor in Vienna (1790s), who introduced the H/B alphanumeric system |