accurate

As an adjective accurate

is in exact or careful conformity to truth; the result of care or pains; free from failure, error, or defect; exact; as, an accurate'' calculator; an ''accurate'' measure; ''accurate expression, knowledge, etc.

As an adverb unmistakenly is

in an unmistaken way; validly or accurately.

As adjectives the difference between accurate and unmistaken

is that accurate is in exact or careful conformity to truth; the result of care or pains; free from failure, error, or defect; exact; as, an accurate'' calculator; an ''accurate'' measure; ''accurate expression, knowledge, etc while unmistaken is not mistaken; valid or accurate.