A couple of months ago, I decided to use a service to check the reliability of NFT. I have tested it and it does not work well so far.
For example, for many tokens normally implemented according to the 721st standard, it cannot determine the URI of the metadata at all, although the tokenURI () function in the contract of these tokens works fine.
Therefore, I would advise you to study the information on each project yourself, google, contact the developers on twitter or discord, or study the smart contract on Etherscan.
This is a small overview of ways to store metadata and media for the most popular NFT platforms.
ArtBlocks
Metadata and media are stored on the blockchain
AsyncArt
Hash for metadata and for media - IPFS.
infiNFT
Metadata is on the blockchain.
KnownOrigin
Hash for metadata and for media - IPFS.
NiftyGateway
Metadata: The collection name and artist name are stored on the blockchain. Some job titles are on the blockchain, some off-chain.
OpenSea
LazyMinting technology makes it difficult to uniquely hash a resource. Metadata and art are stored in the project’s own repository.
Rarible
Hash for metadata and for media - IPFS.
It is my hope that ZKSwap implements all of the NFT authentication tools on one platform.
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