A Beginner’s Guide to ERC721 and ERC1155 NFT Standards

Non-fungible tokens (NFTs) have become one of the most talked-about uses of blockchain technology. Behind the colorful digital art and in-game collectibles are technical standards that define how these tokens work. Two of the most widely used standards are ERC721 and ERC1155.

If you’re new to blockchain or NFTs, the names may sound complex, but understanding them is key to knowing how digital assets are created, stored, and traded. This guide explains both standards in clear terms, using real examples to show how they differ and why they matter.

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What Are NFT Standards?

On the Ethereum blockchain, NFTs are created using “smart contracts,” which are programs that run exactly as coded. To make sure NFTs are compatible with wallets, marketplaces, and other applications, developers follow token standards.

These standards define:

• How ownership is tracked.

• How tokens can be transferred.

• What information is stored (such as artwork or game item data).

Standards ensure that an NFT created by one developer can still be recognized by platforms built by others. Think of them like a universal file format — if you save an image as .JPEG, almost any app can open it.

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Understanding ERC721: The First NFT Standard

ERC721 was the first widely adopted standard for NFTs on Ethereum. It was introduced in 2018 and quickly became the backbone of early NFT projects.

Key characteristics of ERC721:

1. One token equals one unique asset – Each NFT has its own ID, making it distinct from every other token.

2. True non-fungibility – Unlike cryptocurrency coins or tokens that are interchangeable, ERC721 tokens cannot be replaced with each other on a 1:1 basis.

3. Simple ownership tracking – Each token belongs to a single wallet address at any given time.

Examples of ERC721 in use:

• CryptoKitties: One of the first NFT games where each cat is a unique token.

• Bored Ape Yacht Club (BAYC): Each digital ape is an individual ERC721 token.

Advantages of ERC721:

• Clear and simple standard widely supported by marketplaces like OpenSea and Rarible.

• Perfect for digital art and collectibles where each item is completely unique.

Limitations of ERC721:

• Inefficient for large collections because each token must be created and stored separately.

• High gas fees on Ethereum when minting or transferring many tokens at once.

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Understanding ERC1155: The Multi-Token Standard

ERC1155 was introduced later as a way to make NFTs more flexible and cost-efficient. It is often called a “multi-token standard” because it can handle both unique and identical assets within a single smart contract.

Key characteristics of ERC1155:

1. Supports multiple token types – A single contract can hold NFTs, semi-fungible tokens, or even fungible tokens simultaneously.

2. Batch transfers – You can send multiple tokens in one transaction, reducing gas fees.

3. More efficient storage – Instead of deploying a new contract for every NFT, all items can live in one contract.

Examples of ERC1155 in use:

• Axie Infinity: Some in-game items are unique NFTs, while others are identical and tradable in bulk.

• Gods Unchained: Digital trading cards that may have copies, but rare ones still act like NFTs.

Advantages of ERC1155:

• Lower costs for creating and transferring tokens in bulk.

• Useful for games and applications with many assets of different types.

• Can handle both fungible (like in-game currency) and non-fungible assets at once.

Limitations of ERC1155:

• Slightly more complex for developers to implement than ERC721.

• Not as universally supported on older platforms compared to ERC721.

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ERC721 vs ERC1155: How Do They Differ?

To see the differences clearly, here’s a practical comparison:

Feature	ERC721 (Single Asset)	ERC1155 (Multi Asset)
Uniqueness	Every token is unique	Can be unique or identical
Transaction Cost	Higher for multiple tokens	Lower because of batch transfers
Use Case	Digital art, rare collectibles	Games, mixed asset collections
Complexity	Easier to understand and build	More flexible but slightly advanced
Support	Widely recognized everywhere	Gaining strong adoption quickly

Simple analogy:

• ERC721 is like making individual certificates for each painting in an art gallery.

• ERC1155 is like having one system to register both original paintings and mass-printed posters at the same time.

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When to Choose ERC721 vs ERC1155

Choose ERC721 if:

• You are creating a small collection of unique art pieces.

• Your project does not need to mint many tokens at once.

• You want the simplest standard with broadest marketplace support.

Choose ERC1155 if:

• You are building a game or app that has many items, both rare and common.

• You need to mint or transfer assets in bulk to save on fees.

• You want one contract to manage multiple types of tokens.

Both standards can coexist in the NFT ecosystem. In fact, some projects use a mix depending on their needs.

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How These Standards Shape the NFT Market

These token standards are not just technical details — they shape how NFTs function in real-world applications:

• Marketplaces: Platforms like OpenSea and LooksRare use these standards to verify authenticity and enable easy trading.

• Wallets: Wallets such as MetaMask and Trust Wallet rely on ERC721 and ERC1155 compatibility to display NFTs correctly.

• Gaming and Metaverse projects: These standards make it possible to own items that can be traded or moved between platforms.

The introduction of ERC1155 has encouraged developers to experiment with hybrid assets. For example, a single game could issue special one-of-a-kind weapons as ERC721 tokens while using ERC1155 for consumable items like potions or ammunition.

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Key Insights for Beginners

• ERC721 is best for fully unique tokens like digital art or rare collectibles.

• ERC1155 is best for projects that need efficiency and flexibility, such as video games or collections with mixed rarity.

• Both standards are recognized by major NFT platforms, ensuring that assets built with them remain tradable and visible to users.

• Gas fees and scalability are major factors influencing which standard developers choose.

Understanding these standards helps you see beyond the artwork or digital item itself. You gain insight into how ownership is recorded, how tokens move between wallets, and why certain NFTs behave differently than others.

By learning ERC721 and ERC1155 at a beginner level, you build a solid foundation for exploring NFTs more deeply — whether as a collector, developer, or investor.