What is OpenSea? – The Leading Marketplace in the NFT Industry

OpenSea is one of the world’s largest NFT marketplaces, founded in 2017. It has facilitated trading in a wide variety of NFTs such as digital art, game items, collectibles, music, and virtual land. Alongside Ethereum, it supports multiple blockchains like Polygon, Solana, Arbitrum, and Optimism, offering an environment where users can trade at low cost. The transaction fee is kept at an industry-standard 2.5%, and there is no listing fee, making it easy for beginners to sell their NFTs.

In 2023, they launched “OpenSea Pro” for professional traders, providing features such as cross-marketplace trading. They also introduced the “Seaport” protocol, an in-house improvement in smart contracts aimed at reducing gas costs, creating a more efficient trading environment. As the NFT market constantly evolves, OpenSea continues to innovate amid competition, serving as the global standard for NFT trading, supported by many users worldwide.

Key Features and Strengths of OpenSea

OpenSea has established itself as a leader among NFT marketplaces due to its convenience and wide range of features. First, it handles an extremely broad spectrum of NFT categories—digital art, game items, music NFTs, virtual land, domain name NFTs, and so forth. High-profile collections like CryptoPunks and Bored Ape Yacht Club see active trading here, positioning OpenSea as a major marketplace in the NFT space.

Another key characteristic of OpenSea is its open market, where anyone can easily list and purchase NFTs. While some other platforms require listing approvals, OpenSea allows immediate NFT sales simply by connecting a wallet. This accessibility attracts a large community of creators and collectors.

From a cost perspective, OpenSea is also appealing. It charges zero listing fees and a 2.5% selling fee, which is standard in the industry. Moreover, by leveraging L2 blockchains such as Polygon and Arbitrum, they’ve structured a system where gas fees are substantially lowered. This is particularly advantageous for users facing high gas costs on Ethereum’s mainnet, as using Polygon can bring transaction fees close to zero.

Additionally, OpenSea is bolstering multi-chain support, covering over 17 blockchains such as Ethereum, Polygon, Solana, Avalanche, Optimism, and Arbitrum. This lets users choose the chain that best fits their needs, optimizing cost and speed for an ideal trading environment.

OpenSea Officially Launches Next-Gen Marketplace “OpenSea2”

In 2025, the leading NFT marketplace OpenSea formally released a new platform called “OpenSea2 (OS2)”. An evolution of the traditional OpenSea, OS2 aims to shape a more sustainable NFT market through improved user experience and an overhauled reward system. Compared to the old OpenSea, OS2 features a more efficient fee structure, a refined user interface, and an enhanced rewards program.

A particularly notable innovation is a new reward system called “XP Shipment.” Previously, XP was granted for listing or bidding, but that has been discontinued and replaced by a mechanism granting XP for purchasing NFTs and holding them long term. For example, if you hold an NFT from a high-volume project for three months or more, your XP multiplier increases, encouraging long-term market stability.

Furthermore, OS2 refines liquidity incentives, working toward an ecosystem where users can earn fair rewards while maintaining the sustainability of the overall NFT market.

How OpenSea Works

NFT transactions on OpenSea are executed via smart contracts running on the blockchain. First, users connect their wallets (e.g., MetaMask or Coinbase Wallet) to OpenSea to set up for transactions. After that, if they want to buy an NFT, they can either buy at a fixed price immediately or place a bid in an auction. Sellers choose either a fixed-price or auction format and simply set a desired price to list NFTs quickly.

Once a transaction is completed, the smart contract transfers the seller’s NFT to the buyer’s wallet, with payment settling simultaneously. This process is recorded transparently on the blockchain and cannot be tampered with, ensuring secure trading. OpenSea also uses a “Lazy Minting” approach: NFTs are not minted on the blockchain at the time of listing; they are minted and transferred only when someone decides to purchase. Creators therefore do not pay gas fees at the time of listing, making it lower-risk to sell NFTs.

OpenSea previously used the “Wyvern Protocol” but migrated to its own protocol “Seaport” in 2022, achieving a substantial reduction in gas fees and offering more flexible trading options. Implementing Seaport has reportedly cut gas fees by up to 35% per transaction, significantly reducing costs for Ethereum-based transactions.

Getting Started on OpenSea

1. Set up a wallet: Create a crypto wallet like MetaMask and install it as a browser extension or mobile app.
2. Connect your wallet to OpenSea: Go to the official OpenSea site and click “Connect Wallet” in the top-right corner to link your wallet.
3. Browse and purchase NFTs: Find an appealing NFT collection and choose “Buy” or “Place Bid” (for auctions). You’ll need tokens on the supported blockchain (Ethereum, Polygon, etc.) to complete a purchase.
4. List (mint) your own NFTs: If you’re a creator, you can upload images, audio, or other files under the “Create” button. Note that minting or selling may sometimes incur blockchain gas fees.
5. Set royalty fees for resale: When listing an NFT, you can define royalties for secondary sales, receiving a portion of revenue each time the NFT is resold.

For more detailed project info, see here.

OpenSea has completed the following rounds of funding:

• January 4, 2018 (Pre-Seed Round): Raised capital from Y Combinator.
• November 2018 (Series A Round): Raised around $10 million from a16z (Andreessen Horowitz) and others.
• March 2021 (Series B Round): Raised about $23 million from a16z and others.
• July 2021 (Series B Round): Raised about $100 million from a16z and others.
• January 5, 2022 (Series C Round): Raised about $300 million at a valuation of $13.3 billion.

Overall, OpenSea’s total funding amounts to around $473 million.

OpenSea’s Native Token “$SEA” Airdrop Plans

OpenSea has announced plans to release its native token “$SEA” in 2025, with an airdrop for users.

Airdrop Overview

• Token Name: $SEA
• Eligibility: Users who have used OpenSea in the past (details TBD)
• Distribution Timeline: Planned for 2025
• How to Claim: After connecting your wallet, you’ll execute “Claim $SEA” on the official site

OpenSea Changes XP Distribution Rules – Ends Listing and Bidding Rewards, Shifts to Purchases and Holding

Previously, OpenSea offered an XP (experience points) program rewarding users for listing and offering on NFTs, but certain users exploited it by conducting manipulative trades to accumulate large XP. Because of this, on February 18, 2025, OpenSea suspended XP for listing and bidding, announcing a transition to a reward system centered on purchasing and holding NFTs.

Below is a post by OpenSea’s CEO, dfinzer.eth (@dfinzer):

Going forward, users who want to accumulate XP on OpenSea should focus on purchasing and long-term holding of NFTs rather than listing and bidding. In particular, holding NFTs from high-volume projects for over three months grants an increased XP multiplier, making a long-term collecting strategy more important.

Additionally, regularly monitoring OpenSea’s official announcements and the latest info on XP Shipments is crucial to understand eligibility requirements. Simply increasing your number of transactions is no longer enough to maximize XP; contributing to OpenSea’s emphasis on “a healthy market environment” is key.