What Are ERC-721 and ERC-1155: Standards for Creating NFTs

Introduction to Token Standards on Ethereum

One of the fundamental ways to represent exchangeable value in a blockchain network is through asset tokenization. Assets can be either fungible or non-fungible in nature. Fungibility means that tokens can be divided and exchanged for others of the same type, like traditional currencies. On the other hand, non-fungible tokens (NFTs) cannot be divided, and each one is unique with no existing duplicates. In the Ethereum blockchain ecosystem, two prominent standards have emerged for creating NFTs: ERC-721 and ERC-1155.

The ERC-721 standard is a non-fungible token protocol written in Solidity for the Ethereum blockchain, enabling developers to tokenize ownership of any arbitrary data. Meanwhile, ERC-1155 represents an enhanced standard that facilitates the creation of both fungible and non-fungible tokens within a single smart contract interface. Understanding the differences between these standards is crucial for developers and collectors in the NFT space.

What Is ERC-721?

ERC-721 is a non-fungible token standard written in the Solidity programming language for the Ethereum blockchain. This standard allows developers to tokenize ownership of any arbitrary data, creating unique digital assets that cannot be replicated or subdivided. The ERC-721 standard was created by William Entriken, Dieter Shirley, Jacob Evans, and Natasia Sachs in 2018, marking a significant milestone in the development of blockchain-based digital ownership.

Essentially, each ERC-721 token is unique and represents a single, distinct asset. This uniqueness is what makes ERC-721 tokens ideal for representing digital art, collectibles, virtual real estate, and other one-of-a-kind items. The standard enables developers to create an entirely new ecosystem of tokens on the Ethereum blockchain, where each token has its own identity and characteristics.

The ERC-721 standard has become the foundation for many popular NFT projects and marketplaces, establishing itself as the pioneering protocol for non-fungible tokens. Its widespread adoption has proven the viability of blockchain-based digital ownership and created new economic opportunities for artists, creators, and collectors worldwide.

Characteristics of ERC-721 Tokens

The ERC-721 standard structurally resembles the architecture of ERC-20 tokens in many ways. Although the smart contracts of both token types have several similar functions, some functions of ERC-721 are distinctly different to accommodate the non-fungible nature of these assets.

Here are the most characteristic features of ERC-721:

Token Name: Each ERC-721 token has a name field that specifies the token's name for external applications or contracts. This allows for easy identification and branding of NFT collections, making them recognizable across different platforms and marketplaces.

Ownership Rights: The ERC-721 standard includes a specific function field that defines ownership of the underlying token and provides instructions on how to transfer that ownership. This ensures secure and transparent transfer of digital assets between parties, with all transactions recorded immutably on the blockchain.

Token Tracking: The ERC-721 standard has a field called "tokenOfOwnerByIndex" that allows developers to track tokens using a unique identifier. This functionality is essential for managing collections and enabling users to view all tokens they own in a single interface. Each token receives a unique ID that distinguishes it from all other tokens in the contract.

These characteristics work together to create a robust framework for representing unique digital assets on the blockchain, ensuring authenticity, provenance, and secure ownership transfer.

What Is ERC-1155?

ERC-1155 is an enhanced token standard that emerged after ERC-721, representing another significant innovation in the Ethereum blockchain ecosystem. This standard facilitates the creation of both fungible and non-fungible tokens within a single smart contract interface. The primary goal of ERC-1155 is to create a unified smart contract interface that can represent both token types efficiently.

The ERC-1155 standard incorporates the same functionality as both ERC-721 and ERC-20 tokens, but it significantly improves upon both standards in terms of efficiency and versatility. One of the most notable advantages is that transactions using the ERC-1155 standard can be batched together, substantially reducing the cost of trading tokens and minimizing network congestion.

This multi-token standard is particularly useful for gaming applications, where users might need both unique items (like special weapons or characters) and fungible resources (like in-game currency or common materials) within the same ecosystem. By consolidating multiple token types into a single contract, ERC-1155 streamlines development and reduces deployment costs.

Advantages of ERC-1155 Tokens

The ERC-1155 standard stands out with the following distinctive characteristics:

Efficient Transfers: The ERC-1155 standard allows users to perform batch transfers of tokens within a single smart contract. Developers can choose to transfer multiple tokens in one operation, whether they are fungible or non-fungible. This not only reduces transaction costs significantly but also minimizes the impact on the network by consolidating multiple operations into a single transaction. For example, a user could transfer ten different NFTs and 1,000 fungible tokens in one transaction instead of eleven separate transactions.

Multiple Tokens in One Contract: Each ERC-1155 contract describes the existence and operation of both fungible and non-fungible token types simultaneously. ERC-1155 can create one or multiple NFTs while also describing fungible tokens—all within the framework of a single contract. This flexibility eliminates the need to deploy separate contracts for different token types, saving gas fees and simplifying the development process.

Safe Token Transfers: The ERC-1155 token standard includes a built-in function that verifies whether a transaction is valid or not. If a transaction fails validation, this function automatically returns the tokens to the sender. This safety mechanism is particularly helpful when users accidentally make transcription errors or send tokens to incorrect addresses. The standard includes callback functions that ensure receiving contracts can properly handle the tokens, preventing permanent loss of assets.

These advantages make ERC-1155 particularly attractive for developers building complex applications that require multiple token types, such as gaming platforms, metaverse projects, and multi-asset marketplaces.

ERC-721 vs ERC-1155: Key Differences

Smart Contract Architecture

The ERC-721 standard produces exclusively NFTs and requires developers to create a separate smart contract for each new token collection. This means that if a project wants to launch multiple NFT collections, it must deploy multiple contracts, each with its own deployment cost and gas fees. In contrast, ERC-1155 allows developers to design a single smart contract that can be used for minting both fungible tokens and NFTs. This unified approach significantly reduces deployment costs and simplifies contract management.

Efficiency and Cost

Since ERC-721 allows only one operation per transaction, it is relatively expensive and time-consuming when dealing with multiple tokens. This limitation reduces the efficiency of the blockchain network and results in redundant code execution. Each token transfer requires a separate transaction, leading to higher cumulative gas fees for users managing large collections.

In contrast, ERC-1155 allows multiple operations within a single transaction, making it possible to transfer dozens or even hundreds of tokens at once. Therefore, transactions are cheaper and more efficient overall. Additionally, unlike ERC-721, which uses significant storage space on the blockchain for each individual contract, ERC-1155 uses less storage space in the blockchain network by consolidating multiple token types into a single contract. This efficiency becomes particularly apparent in applications with high transaction volumes.

Which Is Better: ERC-721 or ERC-1155?

Both token standards are capable of minting NFTs, and the choice between them largely depends on your personal preferences or specific use case requirements. Some art collectors purchase only ERC-721 NFTs because they consider this token type to be the gold standard in the NFT space, valuing its historical significance and widespread recognition. These collectors may prefer the simplicity and proven track record of ERC-721.

Other collectors and developers have no particular preference and choose based on practical considerations. ERC-1155 is generally cheaper and more efficient, as it reduces gas fees through batch operations, making it an acceptable and accessible way to create NFTs, especially for projects that require multiple token types or high transaction volumes.

For game developers and metaverse projects that need both unique items and fungible currencies, ERC-1155 offers clear advantages. However, for traditional digital art collections where each piece is truly unique and standalone, ERC-721 may be more appropriate and align better with collector expectations.

Ultimately, the decision should be based on factors such as project requirements, budget constraints, user expectations, and the specific features needed for your application. Both standards have proven themselves in the market, and each continues to play an important role in the evolving NFT ecosystem.

FAQ

What is the difference between ERC-721 and ERC-1155?

ERC-721 is a non-fungible token standard where each token is unique. ERC-1155 supports both fungible and non-fungible tokens in one contract. ERC-1155 is more efficient, allowing multiple token transfers in a single transaction.

What is the ERC-721 standard and what are its characteristics?

ERC-721 is the NFT standard where each token is unique and non-fungible. It enables tokens with different attributes, values, and metadata. Tokens are transferable and individually identifiable on the blockchain.

What is the ERC-1155 standard? What advantages does it have compared to ERC-721?

ERC-1155 is a multi-token standard supporting both fungible and non-fungible tokens in a single contract. Compared to ERC-721, it enables batch transfers reducing gas costs, supports multiple token types simultaneously, and allows token recovery if sent to wrong addresses.

How to create NFT using ERC-721?

To create an ERC-721 NFT, host your digital asset on IPFS, write a smart contract using OpenZeppelin libraries, deploy it on Ethereum blockchain, and mint tokens by calling the contract's minting function with metadata URI.

How to create homogeneous and heterogeneous tokens using ERC-1155?

Define token IDs for each type, deploy the ERC-1155 contract, then mint tokens using standard functions. Set supply limits for fungible tokens and unique IDs for non-fungible tokens within a single contract.

What is ERC-721 suitable for? What are its application scenarios?

ERC-721 is ideal for unique digital assets like NFT art, collectibles, gaming items, and virtual real estate. Its non-fungible nature ensures each token is distinct and irreplaceable, perfect for ownership verification and trading of one-of-a-kind items.

What is ERC-1155 suitable for? What are its application scenarios?

ERC-1155 manages multiple token types efficiently in single transactions, ideal for gaming assets, NFT marketplaces, metaverse platforms, and multi-token trading systems requiring batch operations and reduced costs.

Do you need to know programming to create ERC-721 NFTs?

No, you don't necessarily need programming skills. You can use existing library contracts like 0xcert/ethereum-erc721, import them directly, and leverage their built-in functionality without writing code from scratch.

Which is cheaper and more gas-efficient: ERC-721 or ERC-1155?

ERC-1155 is more gas-efficient than ERC-721. It can reduce gas fees by up to 90% by handling multiple tokens in a single transaction, making it the cheaper option for most use cases.

Can ERC-721 and ERC-1155 be implemented simultaneously in the same contract?

Yes, you can implement both ERC-721 and ERC-1155 in a single contract. ERC-1155 supports managing multiple token types, including non-fungible tokens, making it compatible with ERC-721 functionality for unified asset management.