> ## Documentation Index
> Fetch the complete documentation index at: https://kleros.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Proof of Humanity

> Proof of Humanity verifies unique humans on-chain with video, social vouching, and Kleros disputes, powering fair airdrops, voting, and UBI.

# Proof of Humanity

<img src="https://mintcdn.com/kleros/QE-4QbCPMZFNGo_E/images/poh-hero.png?fit=max&auto=format&n=QE-4QbCPMZFNGo_E&q=85&s=6a9910554425c0a12e5f794905b5f33a" alt="Proof of Humanity Interface" width="2990" height="1716" data-path="images/poh-hero.png" />

<Warning>
  Proof of Humanity uses the **Kleros V1 protocol** for dispute resolution even the "PoH 2.0" product version. The "2.0" refers to product improvements (cross-chain support, improved UX), not the underlying Kleros arbitration protocol version.
</Warning>

**Proof of Humanity (PoH)** is a Sybil-resistant registry of verified humans. It combines video verification, social vouching, and Kleros dispute resolution to create a decentralized identity system where each registered person is cryptographically linked to a unique Ethereum address.

PoH serves as the foundation for applications that need to distinguish real humans from bots and duplicate accounts enabling fairer airdrops, one-person-one-vote governance, and universal basic income distribution.

***

## How It Works

<Steps>
  <Step title="Submit a Profile">
    Register by submitting a video of yourself holding your Ethereum address, along with a name and photo. A deposit is required to deter spam.
  </Step>

  <Step title="Get Vouched">
    An already-registered human must vouch for you. Vouching is a web-of-trust mechanism: the voucher stakes their reputation on your legitimacy.
  </Step>

  <Step title="Challenge Period">
    Your submission enters a challenge period. Anyone can challenge your registration (e.g., claiming you're a duplicate or the video doesn't meet requirements) by paying a challenge deposit. Challenges are resolved by Kleros Court.
  </Step>

  <Step title="Registration">
    If unchallenged (or if you win the dispute), you're registered as a verified human. Registration has an expiration period after which you must re-verify.
  </Step>
</Steps>

***

## PoH 2.0 (Product Update)

The PoH 2.0 product update introduced several improvements to the registration experience:

**Cross-chain profiles**: Profiles can exist on multiple chains (Ethereum, Gnosis Chain), enabling use across different ecosystems.

**Improved UX**: Simplified registration flow, better video guidance, and clearer status tracking.

**Enhanced vouching**: Refined vouching mechanics to strengthen the web-of-trust.

<Note>
  These are product-level improvements. The underlying dispute resolution still uses Kleros V1 contracts on Ethereum mainnet.
</Note>

***

## Use Cases

**Sybil-Resistant Governance**: PoH-gated voting ensures one person = one vote, preventing token-whale domination. The Kleros yellow paper describes a future court mode where juror selection requires PoH registration.

**Universal Basic Income**: The UBI token project distributes a universal basic income stream to every registered PoH human.

**Fair Airdrops**: Projects can use PoH to ensure airdrop tokens go to unique humans rather than bots farming with multiple wallets.

**Identity Verification**: Any application that needs to verify a user is a unique human without relying on centralized KYC providers.

***

## What's Next?

<CardGroup cols={2}>
  <Card title="Register on PoH" icon="user-check" href="https://v2.proofofhumanity.id/">
    Start your Proof of Humanity registration
  </Card>

  <Card title="PoH Integration Guide" icon="code" href="/developers/products/poh">
    Verify human users in your application
  </Card>
</CardGroup>