BEP-721

Intermediate

BEP-721 is a BNB Smart Chain (BSC) token standard that allows for the creation of non-fungible tokens (NFTs). It’s an extension of Ethereum’s ERC-721, one of the most commonly used NFT standards and is compatible with the Ethereum Virtual Machine (EVM). Each NFT is unique and is not interchanged with any other token.

BEP-721 tokens allow you to tokenize the ownership of data and attach to it a unique identifier. This aspect makes the token one of a kind and vastly different from BEP-20 tokens. With BEP-20, developers can create multiple identical tokens within one smart contract. However, with BEP-721, each token is assigned a different token ID.

Through these unique IDs, BEP-721 tokens can be used to represent collectible, non-fungible items. Users can trade and transfer these tokens based on their market value, which depends on the token’s rarity or utility.

BEP-721 tokens can represent:

Digital and physical art
Collectibles
In-game items
Physical property and real-estate
Lottery tickets

Like other tokens on BNB Smart Chain, BEP-721 token transfers require BNB for gas fees. BEP-721 tokens can be created on various platforms in the BSC ecosystem, including the Binance NFT Marketplace, Featured By Binance, BakerySwap, and Juggerworld.

BEP-721 token functions

BEP-721 has a list of functions that govern how the token interacts with the BNB Smart Chain. Some of these are fairly standard and are also present in the BEP-20 standard:

name: Defines the BEP-721 token’s name, which other contracts will identify it by
Symbol: A shorter name for the token similar to a ticker symbol
balanceOf: Shows the token balance of a specific address
totalSupply: Defines the total number of the tokens created.

There’s also a set of basic ownership functions, some of which are optional to include. A unique feature for NFTs is the metadata function:

tokenMetadata: This function allows for the inclusion of metadata into a token used to link to an artwork file or another collectible aspect of the NFT.

For example, each CryptoPunk has metadata contained within the NFT that points it to a particular punk in a grid of 10,000 punks. Although CryptoPunks don’t use the BEP-721 token standard, their use of metadata is the same.