Inkan: A Japanese Signature

How do you prove something is original?  In the West we still rely on signatures, though with the decrease in the usage of checks and with digital new digital technologies, perhaps even that is fading away.  In Japan, the inkan [seal] takes the place of signature.  Much as seals were used by royalty in England and many other counties, in Japan inkan are used as authentication.  Nearly every official document must be marked by a registered personal seal.  In addition, there are seals for schools, governments, and organizations.

Some seals are simple names in Japanese kanji carved from wood.  Others are full of intricate designs with ancient styles of the modern characters.  Even diplomas use a series of inkan to mark them as original and authentic.


This is a sample used for the diploma at one of my local junior high’s graduation ceremony.  You’ll notice two red stamps. Reddish-orange is the common ink color for inkan. The paper used is heavy and includes fibers from the getto (zerumbet) plant.



The larger, more intricate stamp is formed with one of the oldest styles of kanji known as tensho.



This inkan reads from right to left, top to bottom. Ku me jima cho ritsu / ku me jima chu gak kou / no inkan.




The modern version of these characters would read like this.  In English the inkan read roughly as [Kumejima Town’s Kumeshima Junior High School’s Seal]




The other mark on the diploma is used with contracts and is kanji for keiyaku (契約) which has a meaning described to me as “It’s more than paper, it’s a community.”



The paper of importance is placed either on a copy or register, then stamped with half the inkan imprinting both pages.  For copies, this shows they are both from the same orignator.  For registers, the information is filled in below so that the original can be checked against a record.  Originals can be lined up with the inkan mark on another copy to prove it is genuine.

While it’s not fool-proof, it is an effective way to mark official documents, and is a lot faster than trying to write out all those kanji for a signature.  The use of seals comes from China, and old versions of such official seals can be seen in museums such as Shuri Castle in Okinawa.

If you live in Japan, you’ll need an inkan rather soon.  Here’s my personal seal.  A small stick of carved wood.

  • Theresa Amlong

    Great post. But I always thought these were called hanko. What is the difference between these two words, any idea?

    • Benjamin Martin

      Good question! “In Japan, seals in general are referred to as inkan (印鑑?) or hanko (判子?). Inkan is the most comprehensive term; hanko tends to refer to seals used in less important documents” via

      I’d say hanko is more a general term for ‘seal’ while inkan refers to the personal seals everyone uses. Also, ‘inkan’ is often used as a verb by adding ‘suru’ at the end.

  • Japan Australia

    Still have my original hanko from my first tour in Japan. Back in those days they were required if you wanted to open a bank account in Japan or get a mobile phone.

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