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<\/figure>\n\n\n\nThe size of a hanko affects three things simultaneously: legibility, convention, and institutional acceptance.<\/p>\n\n\n\n
Legibility<\/strong> is the most immediate concern. A hanko impression needs to be readable. If your name in katakana runs to six or seven characters and you order a 10.5mm stamp, the characters will be cramped, unclear, and potentially unacceptable to a bank that compares impressions carefully. Conversely, a very large stamp used for a daily mitomein on a small receipt looks disproportionate and slightly absurd.<\/p>\n\n\n\n Convention<\/strong> matters because Japan has established norms around which size corresponds to which type of seal. These aren’t always hard legal requirements, but they are widely understood by the institutions you’ll deal with. Walking into a bank with a 10.5mm stamp as your ginkoin isn’t automatically rejected, but it may prompt questions, and some banks do specify acceptable size ranges. Following convention signals that you understand how the system works.<\/p>\n\n\n\n Institutional acceptance<\/strong> is the practical ceiling. Some city halls have size requirements for jitsuin registration. Some banks specify ranges for ginkoin. These vary by institution and municipality, but they’re real enough that checking before you order is worthwhile. A stamp that falls outside an institution’s accepted range will need to be replaced\u2014there’s no workaround.<\/p>\n\n\n\n The short version: size is a functional decision, not just a visual one. Getting it right the first time is straightforward once you understand what each dimension is typically used for.<\/p>\n\n\n\n Here’s how the standard sizes break down in practice.<\/p>\n\n\n\n 10.5mm<\/strong> is the smallest commonly used size. It’s typically used for mitomein\u2014everyday, unregistered seals for low-stakes stamping. Delivery receipts, internal office documents, casual forms. For someone with a short name or a common Japanese family name in kanji, 10.5mm produces a clean impression. For most foreigners with names rendered in katakana, this size tends to be too small to accommodate the characters comfortably.<\/p>\n\n\n\n 12mm<\/strong> is the most versatile size and the most commonly recommended for foreigners as a starting point. It works well as a mitomein with room for longer names, and it’s within the acceptable range for ginkoin at most Japanese banks. If you’re ordering one stamp and aren’t sure yet what you’ll need it for, 12mm is the practical default. The impression is large enough to be clearly legible and small enough to look proportionate on standard Japanese forms.<\/p>\n\n\n\n 13.5mm<\/strong> is the conventional size for ginkoin and the lower end of the jitsuin range. If you’re ordering a dedicated bank seal, 13.5mm is a reliable choice that falls comfortably within what most banks accept. It also works for jitsuin in many municipalities. For foreigners with longer names in katakana, 13.5mm gives the engraver more surface area to work with, resulting in a cleaner, more professional impression.<\/p>\n\n\n\n 15mm<\/strong> is solidly in jitsuin territory. For registered seals used in property transactions, vehicle registration, and major legal documents, 15mm is a conventional and widely accepted size. It carries a visual weight appropriate to its legal significance\u2014a 15mm impression on a contract looks formal in a way that a 10.5mm impression simply doesn’t.<\/p>\n\n\n\n 18mm<\/strong> is the largest standard size and is used for corporate seals, formal organizational stamps, or individuals who specifically want a larger registered seal. For most individual foreigners in Japan, 18mm is larger than necessary. It’s worth knowing the size exists, but unless you have a specific reason to go this large, 15mm covers personal jitsuin needs comfortably.<\/p>\n\n\n\n Quick reference:<\/strong><\/p>\n\n\n\n The diameter of your hanko determines how much surface area is available for engraving. This matters more for foreigners than it does for most Japanese nationals, because Japanese family names used on hanko are typically one, two, or three kanji characters\u2014compact by nature. A name rendered in katakana almost always takes up more visual space.<\/p>\n\n\n\n As a general rule, the more characters your name requires in katakana, the larger the stamp you should order.<\/p>\n\n\n\n A two-character katakana name (rare, but possible with very short Western names) fits cleanly at 10.5mm or 12mm. A four-character name\u2014something like “\u30b5\u30e9\u30fb\u30ea\u30fc” (Sara Lee) rendered in katakana\u2014works well at 12mm. A six-character name such as “\u30de\u30eb\u30c6\u30a3\u30f3” (Martin) or “\u30af\u30ea\u30b9\u30c6\u30a3” (Christy) benefits from 13.5mm or larger. Longer names\u2014eight or more katakana characters\u2014should be at 15mm.<\/p>\n\n\n\n The engraving layout also plays a role. Some hanko are engraved with characters arranged vertically in a single column; others use two columns. A skilled engraver will choose the layout that best fits your name in the chosen size. When ordering from a reputable maker, you can often preview the layout before confirming. If that option is available, use it.<\/p>\n\n\n\n A practical scenario:<\/strong> A French resident named “\u30d9\u30eb\u30ca\u30fc\u30eb” (Bernard, seven katakana characters) orders a 12mm ginkoin. The engraving is technically possible but the characters are cramped and the impression looks unclear when stamped. The bank asks to see it again and ultimately accepts it, but the resident wishes they had ordered 13.5mm. A small difference in diameter, a much cleaner result.<\/p>\n\n\n\n One more consideration: some foreigners choose to use only their given name on a mitomein to keep the character count manageable. This is acceptable for informal everyday use but not advisable for a ginkoin or jitsuin, where your name should match what’s on your official documents.<\/p>\n\n\n\n Script choice and size interact with each other, and it’s worth addressing them together.<\/p>\n\n\n\n As covered in broader hanko guides, katakana is strongly preferred for official and semi-official use in Japan. Banks and city offices expect foreign names in katakana, and a stamp in romaji may not be accepted for ginkoin or jitsuin registration. For mitomein used informally, romaji is more flexible\u2014but even there, katakana looks more conventional in a Japanese administrative context.<\/p>\n\n\n\n From a sizing perspective, romaji names on a hanko present a specific challenge. Latin letters at small diameters tend to become difficult to read, particularly with the curved baseline of a circular stamp. Short names in romaji at 12mm can look passable; longer names in romaji at 12mm often look cluttered. If you’re committed to using romaji for a mitomein, sizing up\u201413.5mm or 15mm\u2014generally produces a more legible result.<\/p>\n\n\n\n For katakana, the character-to-size guidance from the previous section applies directly. Katakana was designed for this kind of compact, formal use, and it engraves clearly at standard hanko sizes when the diameter is matched to the character count.<\/p>\n\n\n\n If you’re starting a new role in Japan, ComfysCareer<\/a> can help you secure the job\u2014then come back here to choose the right hanko size for the paperwork you’ll encounter during onboarding.<\/p>\n\n\n\n Before you confirm your order, work through this list. It covers the decisions that most commonly lead to reorders or institutional rejection.<\/p>\n\n\n\n Identify your use case first:<\/strong><\/p>\n\n\n\n Confirm with your institution if applicable:<\/strong><\/p>\n\n\n\n Name format decisions:<\/strong><\/p>\n\n\n\n Material considerations by size and use:<\/strong><\/p>\n\n\n\n Lead time:<\/strong><\/p>\n\n\n\n HankoHub<\/a> provides use-case guidance alongside each product, so you can match the right size and material to your actual situation rather than guessing. Custom orders are carved to your name and specifications, with worldwide shipping.<\/p>\n\n\n\n What size hanko do most foreigners in Japan need?<\/strong> For most foreigners, 12mm or 13.5mm covers the majority of needs. Start with 12mm if you need a general-purpose mitomein. Go to 13.5mm if you’re ordering a dedicated bank seal or have a longer name in katakana.<\/p>\n\n\n\n Does my bank specify a hanko size?<\/strong> Some do, some don’t. Major banks often accept a range (commonly 12\u201315mm for ginkoin), while regional banks may have specific preferences. It’s worth a quick inquiry before ordering a dedicated ginkoin.<\/p>\n\n\n\n Can I use a 15mm stamp as a mitomein?<\/strong> Yes, there’s no rule against it. It will look slightly oversized on smaller forms, but it functions fine. If you already have a 15mm jitsuin and need it to double as an everyday stamp temporarily, it will work\u2014though keeping your registered seal for formal use only is the better long-term approach.<\/p>\n\n\n\n Is 18mm ever appropriate for an individual?<\/strong> Rarely. 18mm is primarily used for corporate or organizational seals. Some individuals with very long names choose it for a jitsuin to ensure full legibility, but for most people 15mm is sufficient.<\/p>\n\n\n\n What happens if I order the wrong size?<\/strong> For a mitomein, it’s a minor inconvenience\u2014you can simply order a replacement. For a ginkoin or jitsuin, ordering the wrong size before confirming with the institution means starting the process over with a new stamp. This is why checking with your bank or city hall before ordering a registered seal is worth the extra step.<\/p>\n\n\n\n Does the size affect how long the hanko lasts?<\/strong> Larger stamps have more material and, with quality construction, tend to be more durable over time. That said, a well-made 12mm stamp in a quality material will outlast a poorly made 15mm stamp in cheap plastic. Material quality matters at least as much as size.<\/p>\n\n\n\n My name is very long in katakana\u2014what should I do?<\/strong> Order at least 13.5mm, and consider 15mm if the character count is eight or more. Also ask the maker about two-column layout options, which can distribute longer names more legibly across the stamp face. When ordering from HankoHub<\/a>, you can specify your name and they’ll advise on the best layout for your character count.<\/p>\n\n\n\nCommon sizes and typical uses<\/h2>\n\n\n\n
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Name length and readability tips<\/h2>\n\n\n\n
Foreign names: Romaji vs Katakana sizing<\/h2>\n\n\n\n
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<\/figure>\n\n\n\nBuying checklist<\/h2>\n\n\n\n
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FAQ<\/h2>\n\n\n\n
Next steps<\/h2>\n\n\n\n
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