Information processing method, information processing device, and recording medium

An information processing device comprising:

• a first obtainer that obtains first transaction record information indicating a record of a transaction involving a transaction item that is performed using a first non-fungible token (NFT), the first NFT indicating that the transaction involving the transaction item is to be performed in a first unit;
• a second obtainer that obtains second transaction record information indicating a record of a transaction involving the transaction item that is performed using a second NFT, the second NFT indicating that the transaction involving the transaction item is to be performed in a second unit different from the first unit;
• and
• an executor that executes processing to determine a market rate between the first unit and the second unit, based on the first transaction record information and the second transaction record information.