When it comes to cryptocurrency, fungible refers to a cryptocurrency’s interchangeability; meaning, fungible assets are identical and of equal value.
For example, ETH is a fungible token, as it can be exchanged on a one-to-one basis (i.e., 1 ETH with another ETH). On the other hand, non-fungible tokens (NFTs) are each unique and have varying value; hence, they are non-fungible tokens.
There are certain requirements for a token to be considered fungible: It must be uniform, equally interchangeable with another, and maintain a standard value.