NFT marketplace

Marketplaces aggregate collections, show listings and floor prices, and let users trade without trusting each other. Sellers sign listings off-chain, often for free, and a buyer's transaction executes the sale through the marketplace's contract, transferring the NFT and the payment in one step. Revenue comes from platform fees on each sale, and many marketplaces also pass creator royalties to artists.

OpenSea dominated the early market, then Blur captured much of Ethereum's trading volume from late 2022 by targeting professional traders with zero fees and token rewards. Magic Eden grew on Solana and expanded to other chains and Bitcoin Ordinals. Aggregators let traders buy across several marketplaces in one transaction, and some brands run their own curated marketplaces.

Competition drove a race to the bottom on fees and royalties, and token incentives encouraged wash trading that inflated volumes. Marketplaces are also prime targets for phishing: malicious listing signatures can let attackers buy a user's NFTs for nearly nothing. Delistings, copyright takedowns and front-end blocks show that even on-chain trading often relies on centralised websites.