How long is the longest whale and what kind of was it?

The longest whale ever recorded is the blue whale (Balaenoptera musculus).

The longest recorded blue whale measured an astonishing 98 feet (30 meters), though this was an exceptional case.

On average, blue whales can reach lengths of 75-85 feet (23-26 meters). They are also the heaviest animals on Earth, weighing up to 200 tons!