guide to erc-721, nft and smartcontract standard

Table of Contents

A Guide to ERC-721: The Rise of Non-Fungible Tokens


Guide to ERC-721, the Non-Fungible Token Standard that is gaining a lot of attention in recent times, thanks to its ability to represent unique digital assets. The Ethereum blockchain is the most popular platform for creating and trading these tokens, and ERC-721 is the most popular standard for creating non-fungible tokens on Ethereum. In this article, we will take a detailed look at ERC-721, its potential use cases, and compare it with other NFT standards.

What are Non-Fungible Tokens?

Non-fungible tokens, or NFTs, are digital assets that are unique and cannot be replaced or exchanged for an identical item. They can represent a wide range of assets, including digital art, collectibles, in-game items, and more. NFTs are stored on a blockchain and can be transferred and traded just like other digital assets, such as cryptocurrencies.

Guide to ERC-721 – What is it?

ERC-721 is a standard for non-fungible tokens on the Ethereum blockchain. It defines a set of rules and functions that a contract must implement to be considered an ERC-721 contract. ERC-721 contracts can mint, transfer, and burn tokens, and they can also define and enforce certain metadata fields for each token, such as token name and symbol. This standard was introduced in 2017 by the Ethereum community to establish a common set of rules for creating and managing non-fungible tokens on the Ethereum blockchain.

Guide to ERC-721 – Use Cases:

Digital Art

  • ERC-721 can be used to mint unique digital artworks, which can be bought, sold, and collected just like traditional art pieces. One of the most famous examples of this is the CryptoKitties project, which allows users to buy, sell, and breed virtual cats represented as ERC-721 tokens.


  • ERC-721 can also be used to mint unique collectible items, such as trading cards, sports memorabilia, and more. One example of this is the Sorare project, which allows users to collect and trade digital versions of soccer player cards.


  • In-game items can also be represented as ERC-721 tokens, allowing players to own and trade them on the blockchain. One example of this is the Axie Infinity project, which allows players to own and trade digital creatures called Axies.

Certificates and licenses:

  • ERC-721 can also be used to mint unique digital certificates, such as degree certificates, licenses, and more.

Guide to ERC-721 – Advantages:

  • Ownership: ERC-721 tokens represent unique digital assets that can be truly owned by the holder. This means that the holder has the right to transfer, sell or destroy the token.
  • Provenance: ERC-721 tokens can be tracked on the blockchain, providing a transparent and immutable record of ownership and transfer history. This allows for verification of authenticity and provenance of the token.
  • Interoperability: ERC-721 tokens can be easily traded and interacted with on the Ethereum blockchain and other platforms, enabling cross-platform interoperability.

Other NFT Standards:


This standard is an evolution of ERC-721, it allows to mint and manage both fungible and non-fungible tokens in the same smart contract. This can be useful for games or marketplaces with a large number of items, because it allows to handle them with a single smart contract.



This standard is similar to ERC-1155 and allows to mint and manage both fungible and non-fungible tokens in the same smart contract. However, it also allows for the creation of “composable” NFTs, where one NFT can contain or reference other NFTs, creating a hierarchy of ownership and value. This can be useful for creating complex digital assets such as virtual worlds or 3D models.


ERC-721 is a powerful standard for creating unique digital assets on the Ethereum blockchain. From digital art to in-game items, ERC-721 has the potential to revolutionize the way we think about ownership and value in the digital world. As the interest in NFTs and ERC-721 continues to grow, it will be exciting to see how this technology is used in the future. With the introduction of other standards like ERC-1155 and ERC-998, it’s clear that the ecosystem of NFTs is constantly evolving and providing more options for developers and users.