Etherscan Information Center: Understanding ERC-721 Tokens and Their Impact

What Does ERC-721 Mean for Token Transfers?

On Ethereum, the ERC-721 standard is designed specifically for non-fungible tokens (NFTs). Unlike fungible tokens (e.g., ERC-20), each NFT is unique and cannot be exchanged on a like-for-like basis. These tokens represent ownership of digital or physical assets, such as:

• Artwork
• Collectibles (e.g., trading cards)
• Event tickets
• Virtual real estate

Ownership is verifiable via blockchain, making ERC-721 ideal for digital scarcity and provable authenticity.

👉 Explore Ethereum’s NFT ecosystem

Why Is ERC-721 Important?

This standard enables:

1. Smart Contract Compatibility: NFTs operate seamlessly with Ethereum-based dApps.
2. Immutable Ownership Records: Transactions are permanently stored on-chain.
3. Diverse Use Cases: From gaming (e.g., CryptoKitties) to digital art markets (e.g., OpenSea).

Core Functions of ERC-721

| Function | Purpose |
|----------------------|--------------------------------------|
| balanceOf() | Checks NFT count in a wallet. |
| ownerOf() | Verifies token ownership. |
| safeTransferFrom() | Moves NFTs between wallets securely. |

Optional Features:

• Metadata (e.g., artwork details)
• Enumerable interfaces for tracking large collections.

Benefits of ERC-721

• Creators: Monetize unique content without intermediaries.
• Collectors: Prove authenticity of rare items.
• Developers: Build interoperable NFT projects.

👉 Learn how to create NFTs

FAQ

Q: Can ERC-721 tokens be divided?
A: No—each NFT is indivisible (e.g., you can’t own half a CryptoKitty).

Q: What’s the cost to mint an NFT?
A: Gas fees vary based on Ethereum network demand.

Q: Who created ERC-721?
A: Dieter Shirley and team proposed it via EIP-721 in 2017.

Conclusion

ERC-721 revolutionized digital ownership, empowering artists, gamers, and developers. For a full list of ERC-721 tokens, visit Etherscan’s NFT tracker.