A lineal measure roughly corresponding to the distance from the elbow to the tip of the middle finger. (Deut. 3:11) There are indications that the Israelites commonly used a cubit of about 17.5 inches (c. 44.5 centimeters), and calculations in this publication are figured accordingly. The Siloam Inscription, for instance, gives 1,200 cubits as the length of the water tunnel built by King Hezekiah. According to the most accurate modern measurement, this tunnel is 1,749 feet (533.1 meters) long. Thus, when taken at face value, these figures yield a cubit of 17.49 inches (44.4 centimeters). Also, numerous buildings and enclosures excavated in Palestine can be measured in whole numbers of this unit, giving further basis for reckoning the cubit at 17.5 inches.
Evidently the Israelites also used a larger cubit that was one handbreadth (c. 2.9 inches, 7.4 centimeters) longer than the “common” cubit. This larger cubit of about 20.4 inches (51.8 centimeters) figured in the measurements of Ezekiel’s visionary temple.—Ezek. 40:5.
Cubit measuring sticks found in Egypt show a cubit of 17.7 inches (45 centimeters) and one of 20.67 inches (52.5 centimeters).