OpenSea API

OpenSea API is a developer API helping users make custom marketplaces with smart contracts easily.

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What is OpenSea API?

Launched by the world’s largest NFT marketplace OpenSea in 2018, OpenSea API is a set of developer tools enabling users to create custom marketplaces powered by Ethereum smart contracts. Developers can create auctions in any currency, including their own tokens, and collect analytics with OpenSea.js. An NFT must be ERC721 or ERC1155 compliant to list on the marketplace. OpenSea is free, but to get an OpenSea API Key, developers need to fill out an application form.

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