The opportunity An NFT marketplace lets people create, buy and sell unique digital items, such as art, collectibles, tickets or memberships, with ownership recorded on a blockchain. Building one involves smart contracts, wallet connections and a fast, easy-to-use front end. This blueprint explains how NFT marketplaces are structured and how we would approach building one, including when an NFT is the right tool at all. What leading platforms do Well-known NFT marketplaces such as OpenSea let users connect their own wallets, browse collections and trade NFTs, while the ownership and transfers are recorded on-chain through smart contracts. Most marketplaces keep only ownership, transfers and payments on the blockchain, and store images and descriptions off-chain, often on decentralised storage. Clear fees, reliable listings and strong security are what users care about most. Key features Wallet connection and sign-in Minting new NFTs and collections Fixed-price listings and auctions Creator royalties on resales Search, filters and collection pages Activity history and ownership records Admin moderation tools Clear fee and network information How it is built 1 Smart contracts NFT contracts for minting and ownership, and marketplace contracts for listings, sales and royalties. 2 Storage Images and metadata stored off-chain, with references recorded on-chain. 3 Indexer and back end Blockchain events are indexed into a database for fast search and collection pages. 4 Front end A clean interface for browsing, buying and selling, with clear transaction steps. 5 Security Automated tests, reviews and an independent audit before launch. Typical technology Smart contracts (EVM-compatible) Next.js React Node.js MySQL AWS Build stages Stage 1 Define the use case Decide what the NFTs represent and who will buy them, and confirm NFTs add real value. Stage 2 Design contracts and fees Plan minting, royalties, fees and ownership rules. Stage 3 Build on a test network Develop and test contracts and the marketplace thoroughly. Stage 4 Audit and launch Independent security review, then a careful launch with monitoring. Risks and how to manage them Smart contract bugs Use well-tested standards, keep contracts simple and get an audit. Legal and tax questions Take legal advice on the NFTs and payments in your target countries. Low demand Validate that buyers want the NFTs before investing heavily. Frequently asked questions What is an NFT marketplace? A platform where people create, buy and sell NFTs, with ownership and transfers recorded on a blockchain. Are NFT images stored on the blockchain? Usually not. Images and metadata are typically stored off-chain, and the blockchain stores a reference to them. Do we need a crypto wallet to use an NFT marketplace? Most marketplaces require a wallet, although some offer simpler sign-in options that create a wallet for the user. Build it with CodecFactory Our Blockchain App Development team can take this blueprint from idea to launch. We start with a free consultation and a written, fixed quote. Get a Free Consultation More blueprints → This blueprint is a research guide based on our study of leading platforms and public information. It is not a client case study. Platform and product names belong to their owners.