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About

A ledger
for human beings.

The simplest way to explain what Jitsuin does: it is a digital ledger that records, in an immutable and verifiable way, that a real human exists — and that their work is genuinely theirs.

"The easiest way to understand Jitsuin is to think of it as a digital ledger — an unchangeable record that puts a human being at the centre."

We are entering an age where AI systems will be part of how we work, negotiate, contract, and create. That is not a future concern — it is already happening. And the single most important thing missing from that picture is a clear, reliable way to know: is the entity I am dealing with a human being, or a machine?

Jitsuin is the first step in answering that question. It is a way for humans to prepare to work with AI-driven systems — to enter contracts with them, to delegate to them, to verify that what they produce was directed by a human with real accountability behind it.

Think about what is coming: AI agents that negotiate on your behalf, systems that autonomously execute deliverables, smart contracts that trigger payments when conditions are met. For any of that to work with genuine fairness and trust, the humans on either end of the arrangement need to be verifiably human — and verifiably trustworthy.

Jitsuin makes that distinction incredibly clear and incredibly easy. When you engage with someone who holds a Jitsuin, two things are immediately true: you know you are engaging with a human being, and you have a transparent record of whether that person has done what they say they will do.

This is not a product about distrust. It is a product about building the infrastructure for a world where humans and AI systems can work together — with each playing to their strengths, and with the humans always knowing exactly where they stand.

We started with Japan's jitsuin tradition because it is the most elegant model of personal identity verification that has ever existed — 2,000 years old, legally binding, impossible to forge, and deeply personal. We gave it the permanence of mathematics. The result is something that is neither purely old nor purely new: it is tried, tested, and now immutable.

57 AD
First recorded use of a Japanese personal seal — the tradition Jitsuin builds on
2,000+
Years of chain of trust already embedded in this system before we added a single line of code
SHA-256
The cryptographic standard anchoring every seal — the same standard that secures financial transactions worldwide

Three things we will not compromise on.

Humans come first

AI is a tool. A powerful one. But in every transaction, every contract, every creative act — a human being is responsible. Jitsuin keeps that human front and centre, with a clear and permanent record.

Privacy is absolute

Your personal data is used to verify you, then discarded. We never store it, sell it, or share it. Your Jitsuin proves you passed verification — it reveals nothing about who you are beyond that fact.

You own your identity

Your Jitsuin is not a subscription. It is not hosted on a server we can switch off. Your identity hash is yours, permanently, derived from data only you hold. No company — including ours — can take it away.