NFT metadata standards

Off-Chain Metadata

An NFT is a unique ID. On-chain data contains this ID coupled with additional important information like ownership, royalties, and more. However, media and metadata are stored off-chain for performance and flexibility. These data must be carefully written to guarantee compatibility across the tools and dApps of the ecosystem. Ternoa Improvement Proposal (TIPs) propose structures adopted from ERC-1155 to ensure this compatibility.

Here below are listed the expected format for each feature:

Basic NFT

{
  "title": "Title of the NFT",
  "description": "Description of the NFT",
  "image": "Hash of the media",
  "properties": {
    "media": {
      "hash": "Hash of the media",
      "type": "Type of the media (file format)",
      "size": "Size of the media"
    }
  }
}

Secret NFT

{
  "title": "(OPTIONAL) Title of the Secret NFT",
  "description": "(OPTIONAL) Description of the Secret NFT",
  "properties": {
    "encrypted_media": {
      "hash": "Hash of the encrypted media",
      "type": "Type of the encrypted media (file format)",
      "size": "Size of the encrypted media",
      "name": "(OPTIONAL) Name of the encrypted media",
      "description": "(OPTIONAL) Description of the encrypted media"
    },
    "public_key_of_nft": "Public key associated with the Secret NFT"
  }
}

Collection

{
  "name": "Name of the collection",
  "description": "Description of the collection",
  "banner_image": "Hash of the collection's banner image",
  "profile_image": "Hash of the collection's profile image"
}

Marketplace

{
  "name": "Name of the marketplace",
  "logo": "Hash of the marketplace's logo"
}