NFT Metadata
The data describing an NFT — its image link, name, and traits — often stored off-chain, with implications for permanence.
NFT metadata is the information defining what an NFT actually represents: the link to its image or media, its name, description, and trait attributes. The on-chain token typically contains a reference to this metadata rather than the media itself, which usually lives on IPFS or a server.
This architecture is the source of NFTs’ most underappreciated risk: if the metadata or the media it points to is mutable, hosted centrally, or not durably stored, the NFT you “own” can change or vanish. Fully on-chain NFTs (storing everything in the contract) are the most robust but rare and expensive. When someone says they “own” an NFT, they own a token pointing to metadata — and how permanent that chain of references is determines whether the ownership is meaningful long-term.