Japanese Multi-Hole (JIS)
Binders & Hole Punching · 7 specs
Direct Answer
The Japanese Loose-Leaf standard (governed by JIS P 0138) specifies a fine multi-hole grid with an exact 9.5 mm (3/8 inch) pitch and 5.5 mm hole diameter, featuring 26 holes for B5 paper and 30 holes for A4 paper. Engineered by stationery manufacturers such as Kokuyo and Maruman, it eliminates paper tear-out entirely.
Source: JIS P 0138 (Paper and Board Loose-Leaf Binder Specifications) / Kokuyo Campus Standards · Last reviewed Aug 28, 2026
Specs
| Hole Pitch (Center-to-Center) | 9.5 mm (0.374 in / approx. 3/8 in) |
| Hole Diameter | 5.5 ± 0.5 mm |
| Edge Margin to Hole Center | 6.5 ± 0.5 mm |
| B5 Paper Hole Count | 26 holes (for 257 mm JIS B5 paper) |
| A4 Paper Hole Count | 30 holes (for 297 mm ISO A4 paper) |
| A5 Paper Hole Count | 20 holes (for 210 mm ISO A5 paper) |
| Primary Applications | Kokuyo Campus Smart Ring binders, Maruman Giuris, King Jim multi-ring loose-leaf notebooks |
The Multi-Ring Engineering Advantage
Because the sheet is held by 26 to 30 individual interlocking rings spaced every 9.5 mm, mechanical stress is distributed across the entire page edge. Ultra-thin 70 gsm Japanese fountain-pen friendly paper (such as Kokuyo Sarasara or Maruman MPS) can be turned hundreds of times without a single hole tearing out, rendering ring reinforcing stickers obsolete.