The "IsTwentyOne" Attestation: Purpose and Limitations

Overview

The "IsTwentyOne" attestation is a statement of fact that confirms a wallet holder is at least 21 years old. This attestation is useful for platforms and services that require age verification, such as alcohol sales, gambling services, or other age-restricted activities.

How It Works

The process follows the standard attestation workflow:

1. Wallet Connection: Connect your Ethereum wallet to Zipwire

2. Age Verification: Complete a Yoti ID check that verifies your date of birth

3. Age Calculation: Zipwire calculates your age from the verified date of birth

4. Attestation Issuance: If you're 21 or older, claim the "IsTwentyOne" attestation

5. Blockchain Recording: The attestation is recorded on the Base blockchain

Attestations

Privacy Features

• The attestation only confirms the age threshold (21+) without revealing your exact date of birth

• No personal data is stored on the blockchain

• The attestation can be verified without exposing additional personal information

How to Get IsTwentyOne Attestations

Attestations

You can obtain IsTwentyOne attestations through:

• Self-service: Use Zipwire Attest for independent registration

• Business integration: Use Zipwire Collect when businesses include ID checks

Use Cases

• Alcohol sales - Verify customers are 21 or older

• Gambling platforms - Ensure users meet age requirements

• Adult content - Age-gate access to mature content

• Financial services - Some services require users to be 21+

Limitations

• Age Threshold Only: Confirms you're 21+, not your exact age

• Transfer Vulnerability: If a wallet is sold or stolen, the attestation remains

• Age Revealing: Unlike some attestations, this does reveal that you're at least 21

• Permanent Record: Once issued, the attestation is permanent on the blockchain

Best Practices

Attestations & Privacy: Timing Your Claims & Data Deletion

• Consider timing: Space out age attestation claims to avoid linking wallet addresses

• Understand permanence: Age attestations are permanent once issued

• Use appropriately: Only require age attestations when necessary for your service

Comparison to Other Attestations

• IsAHuman: Confirms the wallet belongs to a real person (no age information)

• IsTwentyOne: Confirms the user is at least 21 years old

• Private Data Attestations: Allow selective disclosure of specific age information

The "IsAHuman" Attestation: Purpose and LimitationsThe "Private Data" Attestation: Merkle Roots