Although morphology varies greatly within the family, the Chiroteuthidae are distinguished by their extremely elongated bodies and (in most species) tentacles; the latter may be up to four times the mantle length in Asperoteuthis acanthoderma.

With a lower density than the surrounding seawater, the ammonium chloride helps chiroteuthids to conserve energy reserved for swimming by maintaining the body's neutral buoyancy.

[3] The distinctive doratopsis paralarvae are thought to remain within the first few hundred meters of the water column, where they likely feed on zooplankton and slowly undergo a marked transformation to subadults.

During the doratopsis stage, the paralarval chiroteuthid possesses a greatly elongated gladius (internal shell) extending well beyond the fins; this supports a long, trailing, tail-like structure that is further adorned with—depending on the species—either a pair of large oval or heart-shaped "secondary fins", a series of small flaps running the length of the tail, or a series of oval "bulbs" made buoyant by low-density fluids.

The elongated neck and brachial pillar are chambered, and vesicular tissue is present in the posterior end of the mantle and (in advanced stages) in the arms.

During the paralarva's transformation into a subadult, its arms also become elongated (but remain subequal in some species) along with other changes in body proportions; photophores are developed, and the paralarval club is resorbed and replaced with an adult form.