A designated marksman rifle variant with a folding under-barrel bipod and Trijicon ACOG 4× magnification sight was also made but later phased out in favour for the Tavor TAR Flattop.

[8] The objective of the project was to create an assault rifle that was more reliable, durable, and easier to maintain than the M4A1 carbine, while also being better suited to close-quarters combat and mechanized infantry roles.

Due to the military's close-quarters and mechanized infantry requirements, the project team selected a bullpup design that would allow the weapon to be compact while keeping a long barrel able to achieve ballistically favourable high muzzle velocities.

[8] A long-stroke piston system, similar to that found in the AK-47 and M1 Garand, was selected to ensure the weapon's reliability under adverse conditions.

Qualities tested included Mean Rounds Between Failures (MRBF), reliability, ergonomics during long marches, and ease-of-maintenance.

[5] As part of initial testing by Israel Defense Forces' infantry units, the TAR-21 was distributed to members of the training company of the Tzabar Battalion from the Givati Brigade who were drafted in August 2001.

[9] Issues with fine sand entering the Tavor TAR's chamber, which were identified over the two years of testing, were rectified by numerous small adjustments.

The weapons division of the Ground Forces Command was quoted as saying that it's "very satisfied by its capabilities... the rifle performs very well and has proven itself.

Due to its bullpup design the receiver, bolt carrier group, and magazine are placed behind the pistol grip.

As a result, the Tavor provides carbine overall length, yet can achieve rifle muzzle velocities if equipped with a rifle-length barrel.

[15] An issue related to this is the original plastic cover on the unused ejection can allow gas to escape during the course of fire.

[17] This is a request of modern armies, as it helps to allow soldiers to know when their magazine empties and to reduce reloading times during combat while also not requiring manual action cycling after.

[18] The Tavor barrels are made from CrMoV steel and cold-hammer-forged (CHF) on the premises of the IWI factory in Ramat HaSharon.

The CTAR-21 is a compact shorter 380 mm (15 in) barrel variant intended for commandos and special forces, but has become more favoured than the standard TAR-21 throughout the IDF.

In Europe, the Czech company Zeleny Sport recently (December 2015) imported Israeli-made TC-21s, equipped with Mepro M5 or M21 reflex sight, which are now available for both civilian and law enforcement customers.

[31] IWI US sells the Tavor SAR in variety of variants:[32] Note: IWI US sells their Tavor SARs in a variety of colours, including Black (B), Flat Dark Earth (FD), and OD Green (G); the letter "B" subsequent to "TS" in the rifles' designations can be switched with any of the colours' respective letters.

A significant aftermarket of spare and replacement parts has developed around the Tavor rifle family, including the development of match grade accurizing triggers for the bullpup rifle that are produced by manufacturers such as Geissele Automatics and double stage trigger pack TAV-D from Shooting Sight.