Something that can't be counted — because it's too big, or it just can't be pinned down that way — is incalculable. A kindergarten class's excitement on Halloween is incalculable.
The depth of your love for your cat might be incalculable, and so is the concept of infinity. Things that can't be accurately measured can be described with the adjective incalculable, as can things that aren't predictable: "His anger over the dent in his car was incalculable. The root of the word is calculate, or count, which comes from the Latin calculare, "to reckon, or to compute."