Open Sea NFT

When we talk about blockchain technology and cryptocurrencies, most people tend to remember Bitcoin, Ethereum, yield farming, and speculation. What many people fail to notice is that the most valuable cryptographic tokens existing today, in terms of scarcity and valuation, are the non-fungible tokens (NFTs).

Initially more suitable for specific applications, such as rare digital items or crypto-based art, nowadays NFTs took the crypto industry by storm, both in the volume of funds and popularity.

Projects such as Sorare (NFT-based fantasy soccer), CryptoKitties, and Crypto Punks demonstrate that the tokenization of the industry of online games and digital art is directly affecting the way people interact with the possibilities brought by the crypto industry.

OpenSea is the world’s first marketplace focused solely on NFTs in general. The project gained more and more prominence throughout the years and currently is the world’s largest marketplace specialized in crypto rarities.

Back to Basics – What Are NFTs?

Non-Fungible Tokens (NFT) are tokens that represent a crypto-asset based solely on uniqueness and scarcity. In this sense, NFTs are tokenized versions of digital or real-world assets.

There are no NFTs that are interchangeable with each other, meaning that they are not like cryptocurrencies such as Bitcoin or Ether, for instance. Plus, it is impossible to counterfeit or replicate an NFT.

ERC-721 tokens are the standard for the issuance and trading of non-fungible assets on the Ethereum blockchain. These rare tokens can be useful in various ways, not only as art collectibles and video games items but also as digital identity, licensing, certificates, documents, deeds, etc.

Currently, two standards are recurrent when it comes to NFTs, ERC-721 tokens and ERC-1155 tokens.

The ERC721 standard was the first of its type to come out years ago.  The first project to capitalize on the possibilities brought by NFTs was CryptoKitties, which in 2017 sparked a massive movement of popularization of NFTs.

The ERC1155 standard was developed to introduce the idea of semi-fungibility to the NFT world. Plus, this type of asset provides further possibilities for minting and building new NFTs, as an ERC-721 token could be built using an ERC-1155.

In this sense, OpenSea was essential to popularize NFTs, rapidly becoming the hottest marketplace of its kind in the crypto industry.

What is OpenSea?

Currently, OpenSea is the largest hub for crypto-collectibles and other rare digital items. So far, the platform counts more than 300 asset types and more than 10 million digital assets on the market.

Founded in late 2017, the marketplace allows users to buy, sell, bid on and collect all types of NFTS available in the crypto market, which includes domain names and membership NFTs.

Plus, anyone with an Ethereum wallet and crypto collectibles is permitted to expose and sell their digital goods on the gallery.

While many individuals tend to rely on NFTs as a way to consume digital art and collectibles, OpenSea upgrades the experience by providing users a great landscape of possibilities, which includes different blockchain-based games (Axie Infinity, Gods Unchained, Sorare, etc.) and other items based on the concept of digital ownership.

Many crypto investors also use the OpenSea gallery as a way to get an idea about the price of different NFTs, using the information to speculate and anticipate the valuation of such digital rarities.

The platform also has plenty of space for developers who want to use their skills to create their unique digital assets. OpenSea permits devs to develop or submit NFTs, creating personal marketplaces for ERC-721s and ERC-1155s.

NFT Trading Was Never that Easy

To buy or sell any digital rarities, OpenSea users must have a digital wallet. MetaMask is the option suggested by the platform, while it also offers compliance with Fortmatic, WalletConnect, WalletLink, Arkane Network, Dapper, Authereum, Torus, and Bitski.

After logging in, users will interact with the homepage dashboard. There are several categories where buyers and collectors should find all types of NFTs, which includes:

  • Art (Rarible, Known Origin, SuperRare, etc.)
  • Domain Names (Unstoppable Domains, Decentraland Names, ENS, etc.)
  • Trading Cards (Sorare, Toshimon, Meme Ltd, Gods Unchained, etc.)
  • Collectibles (Axie Infinity, CryptoKitties, Crypto Punks, ChadsLimited, etc.)
  • Virtual worlds (Decentraland, MegaCryptoPolis, Cryptovoxels, etc.)

OpenSea has the exclusive “New” tab, which users can select to check a weekly resume of the latest collections launched by different developers, creators, artists, and influencers.

After selecting the desired NFT, it is possible vto buy the item directly. In some cases, some collectibles are sold through an auction mechanism. The highest bid at the end of each auction wins, the payment is automatically made, and the winner receives the asset in his wallet.

Exposing and Selling Crypto Rarities

OpenSea Marketplace

Selling ERC-721s and ERC-1155s on OpenSea is not difficult as well. Any user who has non-fungible tokens in his wallet can sell their assets at a specific price or through an auction.

The platform is user-friendly, so users just have to connect their wallets and select the tab “My Items” on the dashboard. Then, it is possible to select the item(s) that will be exposed for selling and click on the “Sell” button.

OpenSea’s mechanism requires sellers to make two initial transactions that only require gas before listing an item for sale. One transaction is required to initialize the account for making sell orders, while the other transaction allows the platform’s smart contract to access the crypto collectible that is being exposed for sale.

Users can set a fixed price for an item or opt to use the platform’s auction mechanism. Plus, it is possible to include an ending price and an expiration date. OpenSea permits users to change the price of items after their listing, charging no extra fees in the process.

When it comes to fees, OpenSea has a fixed 2.5% fee for every successful sale made on the platform.  In some cases, an additional fee may be taken by the developer of the NFT as well.


Focused solely on non-fungible tokens (NFTs), OpenSea is the first and largest marketplace for user-owned digital goods, including digital art, crypto-based collectibles, gaming items, domain names, and other scarce assets.

The platform helped to popularize and expose the valuable aspect of investing in NFTs, highlighting the uniqueness and scarcity of such types of assets.

Currently, both ERC-721 and ERC-1155 can be traded in the immense gallery, helping to create new economies based on true digital ownership.

In essence, OpenSea offers potentialized what NFTs have to offer within a single platform, building an intuitive and user-friendly tool that can be used by anyone. From Sorare soccer cards to contemporary pieces from Known Origin, you can find virtually any existing NFTs within OpenSea.