Incalculable
adjective
Too great or numerous to be computed.
“The loss the National Library suffered from the fire is incalculable.”
Impossible to calculate.
Of a person's mood or character, etc.: impossible to predict.
“He is incalculable when he's drunk. He can turn from an amiable person into a violent horror in a moment.”
Synonyms: incomputable, capricious, fickle, huge