Technical Concepts

ERC-721

Ethereum Request for Comment 721

Standard for creating non-fungible tokens on Ethereum

Definition

ERC-721 is the technical standard for non-fungible tokens (NFTs) on Ethereum. It defines how to create unique, indivisible tokens that can represent ownership of digital or physical assets.

ERC-721 (Ethereum Request for Comment 721) is a technical term used to understand Standard for creating non-fungible tokens on Ethereum. In practice, it matters because it affects how users evaluate protocols, compare opportunities, and avoid hidden assumptions.

Example

CryptoKitties and most NFT collections follow the ERC-721 standard to ensure compatibility with wallets and marketplaces.

1

How it works

In practice, the concept shows up like this: CryptoKitties and most NFT collections follow the ERC-721 standard to ensure compatibility with wallets and marketplaces.

2

Why it matters

ERC-721 matters because small misunderstandings in DeFi can turn into bad pricing, liquidation, governance, custody, or smart-contract risk. A good mental model helps you compare protocols without relying on marketing language.

3

What to check

Treat it as infrastructure: understand what it automates, what trust assumptions remain, and how failures propagate. The main checks are: Standard limitations; Gas costs; Compatibility issues.

Risks to Consider

  • Standard limitations
  • Gas costs
  • Compatibility issues

Common Questions

What does ERC-721 mean in DeFi?

ERC-721 means Standard for creating non-fungible tokens on Ethereum. The useful question is not only the definition, but how the mechanism changes risk, return, liquidity, or governance for the user.

How is ERC-721 used in practice?

A practical example: CryptoKitties and most NFT collections follow the ERC-721 standard to ensure compatibility with wallets and marketplaces.

What should I check before relying on ERC-721?

Check standard limitations, gas costs, compatibility issues. Also verify liquidity, oracle assumptions, admin controls, and whether the protocol has been tested during stressed markets.

Related Terms

Related Articles

Non-fungible tokens explained with Blastoise and Charizard

Non-fungible tokens explained with Blastoise and Charizard

“Non-fungibles” — don’t let yourself be fooled by the mushroom-evoking name, fungibility is an old concept that is finding a second wind nowadays. It’s mostly about collectibles and video games for now, but it will soon outgrow these industries. Indeed, the potential of non-fungibles tokens is much more significant than this: from official documents to titles of ownership, their use cases are diverse and numerous. Let’s start by establishing the basics about non-fungible tokens (NFTs from now on) thanks to Pokémon cards before we dive into their potential use cases and the future developments of the underlying technology.

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