ERC-7866: Decentralised User Profiles
Gravatar for Web3 — A production-ready standard for decentralized, interoperable user profiles on EVM blockchains.
Like Gravatar, but decentralized and on-chain: claim a soul-bound username, set avatars, and sync your identity across Web3 apps with full control and privacy.
What is ERC-7866?
ERC-7866 defines a standard for decentralized user profiles implemented as Soul Bound Tokens (SBTs). These are non-transferable, immutable identity containers that enable interoperable user representation across multiple blockchain networks.
Just like you set a Gravatar once and use it everywhere on the web, ERC-7866 lets you:
- Claim a unique username tied to your address
- Set a global avatar used by default
- Create context-specific avatars for different dApps
- Control visibility of your profile data
- Maintain the same identity across chains and applications
Key Features
- Unique Identities — Claim a human-readable username (
alice@eth.soul) mapped to your address - Cross-dApp Avatars — Set different avatars for different applications
- Privacy Control — Mark avatars as public or private with on-chain enforcement
- Multi-Chain Ready — Same identity format works across Ethereum, Polygon, Arbitrum, and other EVM chains
- Off-Chain Efficient — Metadata stored on IPFS/Arweave with minimal on-chain footprint
- Event-Driven — Full event logging for profile discovery and indexing
Why ERC-7866?
Problem: Every Web3 dApp creates separate profiles. You have no unified identity.
Solution: ERC-7866 provides a standard profile layer that all dApps can integrate with:
- Users create once, reuse everywhere
- Full control over their identity
- Privacy and customization options
- Decentralized, no central authority
Use Cases
- User Identity — Portable identity across Web3 apps
- Gaming — Game-specific character avatars while maintaining core identity
- Professional Profiles — Separate work and personal identities
- Social Discovery — Search users by username or avatar
- Account Recovery — Identity survives wallet loss