Interactive atlas / millimeters

Notebook size comparison

Choose two formats to compare their page footprint. A matching size does not automatically guarantee cover, ring, or refill compatibility.

Same footprint; system check required

A5 compared with Hobonichi Original

Choose two formats and select Compare.

Width difference—

Height difference—

Source unitmm

How to read the result

Verified system means both entries belong to the same manufacturer-defined refill or cover family. Same footprint; system check required means width and height match but thickness, rings, tolerances, or closure design may differ. Not a verified direct fit means this atlas found no official compatibility statement.

The rectangles are scaled relative to each other, not to your screen. Always open the linked guide and current manufacturer specification before ordering.