Adults typically weigh between 70 and 170 grams (2.5 and 6.0 oz)[3] The tail of a kangaroo rat is longer than its body and head combined.

The coloration of kangaroo rats varies from cinnamon buff to dark gray, depending on the species.

[7] The rapid locomotion of the banner-tailed kangaroo rat may maximise energy cost and minimise predation risk.

[8] Kangaroo rats live in arid and semiarid areas, particularly on sandy or soft soils[4] which are suitable for burrowing.

Their elevation range depends on the species; they are found from below sea level to at least 7,100 feet (the type locality of D. ordii priscus).

[9] They are sensitive to extreme temperatures and remain in their burrows during rain storms and other forms of inclement weather.

[11] They do this in part by lowering their metabolic rate, which reduces the loss of water through their skin and respiratory system.

[11] To help conserve water they produce very concentrated urine, via a process apparently associated with expression of aquaporin 1 along a longer than usual segment of the descending limb of the loop of Henle in the kidney.

[4] They have been seen storing the seeds of mesquite, creosote bush, purslane, ocotillo, and grama grass in their cheek pouches.

[15] This is initially done close to the food source, maximizing harvest rates and reducing travel costs, but later redistributed more widely, minimizing theft by other rodents.

[15] Banner-tailed kangaroo rats larderhoard a sizable cache of seeds within the large mounds they occupy.

The burrows have separate chambers used for specific purposes like sleeping, living, and food storage.

To maintain a constant temperature and relative humidity in their burrows, kangaroo rats plug the entrances with soil during the day.

[4] When the outside temperature is too hot, a kangaroo rat stays in its cool, humid burrow and leaves it only at night.

[11] To reduce loss of moisture through respiration when sleeping, a kangaroo rat buries its nose in its fur to accumulate a small pocket of moist air.

[4] There appears to be a dominance hierarchy among male kangaroo rats in competition for access to females.

A Merriam's kangaroo rat female will allow multiple males to mount her in a short time, perhaps to ensure greater chances of producing offspring.