NFT.Storage is a storage service that lets you upload off-chain NFT data for free, with the goal to store all NFT data as a public good. The data is stored perpetually in the Filecoin decentralized storage network and made available over IPFS via its unique content ID. You can upload as much data as you want as long as it's part of an NFT (e.g., metadata, images and other assets referenced in a token or its metadata), although there is currently a limit of 31GiB per individual upload.