NFTs are a game-changing technology, providing ownership for digital assets and serving as certificates for holders or access keys for the underlying
NFTs are a game-changing technology, providing ownership for digital assets and serving as certificates for holders or access keys for the underlying content, which could be music, movies, art, real estate, and a lot of other stuff. However, what makes nonfungible tokens (NFTs) useful in real terms is metadata. It may not be a buzzword exactly but it ensures the user is able to make out what the NFT is all about.
Metadata is information about the content that an NFT represents. As large files cannot be stored on the blockchain for the simple reason that they become too expensive, NFTs, most of the time, just point to the files stored outside the blockchain. That said, only a few NFT artworks are stored on-chain.
This article explains NFT metadata, what makes putting up content on blockchain impractical, and how to find NFT metadata on Opensea and Rarible. Let’s start with understanding what NFT metadata actually is.
What is nonfungible token (NFT) metadata?
An NFT refers to a specific digital asset that could be in the form of a JPEG, GIF or an MP4 file. Though the token itself is hosted on the blockchain, the file underneath is stored off-chain. NFT metadata points out specifications regarding that stored data. It might include information such as the NFT’s name, description of the NFT, transactional history, link to the hosted image, traits and more.
As for the advantages of NFT metadata, it helps solution architects to set aside the technical issues when hosting large files on a chain. The preferred practice is to upload the link of the content to the blockchain while storing content on an HTTP URL on the current Internet or the InterPlanetary File System (IPFS).
IPFS is a file-sharing peer-to-peer (P2P) network for storing and sharing data in a distributed file. The metadata serves as the input of the NFT smart contract one needs to deploy on the blockchain network.
Metadata is specified in a standardized JavaScript Object Notation (JSON) format. Inside the smart contract, though, the information is stored as a Universal Resource Identifier (URI) as storing as a JSON is too demanding on resources. However, users can download NFT metadata at will.
Why is metadata for off-chain data needed?
The large size of images, audio and video content makes uploading it to the blockchain very expensive. For instance, if someone wanted to store one gigabyte of data on the Ethereum blockchain, it would cost an approximate equivalent of $35 million. If a movie of 160 odd minutes is stored on a blockchain, it might cost more than the expenses of making the film, i.e., $237 million.
The URI string, as mentioned above, indicates a location where one can find the token’s JSON description. The relevant metadata stays as a permanent record on the blockchain, describing what the token represents.
What Opensea and Rarible add to the NFT ecosystem?
Huge demand for NFTs led to the need for marketplaces where users can create, transfer and monetize their assets. The marketplaces provide the tools for these activities, which are so crucial for keeping up the NFT movement. Topping the chart are Opensea and Rarible, two open platforms where anyone can mint and trade NFTs.
OpenSea is the world’s first and largest marketplace for NFTs, enabling users to roll out their own NFT collections to sell on the platform. Simplifying the intricate processes required for managing and monetizing NFTs, OpenSea provides the infrastructure for minting, listing and trading NFTs. Initially built to support CryptoKitties, OpenSea has grown to become NFT participants’ go-to marketplace.
Rarible is also a peer-to-peer (P2P) gateway into the NFT market, offering simple minting and trading features. Unlike OpenSea, Rarible deploys its native token, RARI, to govern the platform and enable holders of RARI to vote on critical decisions.
How to view NFT metadata on OpenSea?
Any seasoned trader will want to view NFT metadata on OpenSea to find out what the NFT is all about. Checking metadata on OpenSea is pretty simple. For ease of understanding, let us focus on finding metadata of NFTs based on Ethereum.
The process is as follows:
1. Open the NFT they want to get metadata for.
2. Scroll down and click on the “Details” tab and click the link next to the contract address.
3. In the Etherscan link that appears on the screen, then copy the contract address.
4. The user now types api.opensea.io/asset/ in the URL text box and pastes the copied contract address after slash at the end of the URL, followed by the token ID mentioned in contract details.
The metadata in JSON format appears on the screen. To find metadata of NFTs hosted on other blockchains, one uses a relevant blockchain explorer to get the contract address. For instance, if the NFT is hosted on the Solana blockchain, clicking the link next to “Contact Address” on the “Details” tab takes one to Solana explorer Solscan.io. One can then use the relevant API to get the metadata.
How to find NFT metadata…
cointelegraph.com