Planner systems
Hobonichi Planner Formats and Language Options
Original, Planner, Cousin, HON, Weeks, Day-Free, and 5-Year compared by layout, language, size, and date structure.
Open field guideBungu Atlas / Field guides
Notebook systems, without the guesswork.
Ten research-based guides built around official dimensions and explicit compatibility—not borrowed product opinions.
Refill systems
Hobonichi Size and Cover Compatibility
A conservative compatibility map for Original, Planner, Avec, Cousin, Day-Free, HON, Weeks, and 5-Year Techo formats.
Open field guide
US buying
How to Buy Japanese Notebooks from the US
A source-first buying workflow for official US stores, authorized retailers, imports, marketplace listings, returns, and counterfeit risk.
Open field guide
Refill systems
Japanese Notebook Binding and Refill Systems
A field guide to stitch binding, saddle-stitched inserts, elastic systems, and ring binders—and why equal sizes can still be incompatible.
Open field guide
Size notes
Japanese Notebook Sizes Explained
A practical map of A5, A6, Japanese B sizes, proprietary planner formats, and the measurements that matter before you buy.
Open field guide
Planner systems
Japanese Planner Start Dates: January vs April
How calendar start month, edition language, school-year timing, and release season interact in Japanese planners.
Open field guide
Refill systems
Kokuyo Campus A5 and B5 Binder Compatibility
How size, four-ring Binder Notebooks, conventional loose-leaf hole counts, and paper dimensions interact in the Campus system.
Open field guide
Size notes
MD Notebook Sizes and Layouts
Compare current MD Notebook A7, A6, B6 Slim, A5, and A4 Variant formats with blank, lined, grid, and dot-grid options.
Open field guide
Refill systems
TRAVELER’S Notebook Refill Compatibility Matrix
A system-by-system matrix for Regular and Passport notebook, diary, storage, connection, repair, and archive accessories.
Open field guide
Size notes
TRAVELER’S Notebook Regular vs Passport
Compare the two official TRAVELER’S notebook systems by cover and refill dimensions, portability, paper capacity, and intended use.
Open field guide