Its final height is officially being kept a secret due to competition; however, figures released by a contractor on the project have suggested a height of around 808 metres (2,651 feet). Based on this height, the total number of habitable floors is expected to be around 162. However, on the project's official website, an interior graphic of an elevator panel shows floor numbers up to 195. A more recent article by building subcontractor Persian Gulf Extrusions states a final height "over 940 metres", or at least 3,084 feet, but this has not yet been confirmed by Emaar. This new figure is 24 metres higher than the final height rumoured on burjdubaiskyscraper.com. Another source, from dubaimegaprojects.com reported an estimated final height of 1,011 metres (3,317 ft.) and a floor count of 216 floors.

If all goes according to plan, Burj Dubai will soon become the tallest building and the tallest freestanding structure in the world, beating current title holders CN Tower in Toronto (tallest freestanding structure) and Taipei 101 in Taipei (tallest building), as well as other proposed skyscrapers like the Freedom Tower at New York City's World Trade Center, the Shanghai World Financial Center, and Chicago's Spire. In addition, with a minimum height of 630 m (2,067 ft.), the Burj Dubai will assume the title of the world's tallest structure, surpassing the guyed KVLY-TV mast in North Dakota. It will be nearly twice the height of the iconic Empire State Building.

Though unconfirmed, Burj Dubai has been rumored to have undergone several height increases since its inception. Originally proposed as a virtual clone of the 560 m (1,837 ft) Grollo Tower proposal from Melbourne, the tower was quickly redesigned with an original design by Skidmore Owings and Merrill seen above and discussed below. This design stood put it at approximately 705 metres (2,313 ft). Contradictory information abounds regarding the official height of the building, which is to be expected considering the building seeks to acquire the designation as the world's tallest structure upon completion in 2008. One website mentions a rumored final height of 916 metres (3,005 ft) in a September 28, 2006 posting, but this is contradicted by a September 20, 2006 article listing a height over 940 metres (3,084 ft).

The lead architect, Adrian Smith, felt that the upper-most section of the building did not culminate elegantly, so he sought and received approval to increase it to the currently planned height. It has been explicitly stated that this change did not include any added floors, which is fitting with Smith's attempts to make the crown more slender. However, the top of the tower, from the 156th floor onward or from 585.7 meters (1,922 ft) to the top, will be a steel frame structure, unlike the lower portion's reinforced concrete. The developer, Emaar, has stated this steel section may be extended to beat any other tower to the title of tallest; however, once the tower is complete the height cannot be changed.

As of May 04, 2007, the Burj Dubai was at level 124 and stood 442 meters (1,450 feet) tall. It is tied with the Sears Tower for the title of 4th tallest highrise in the world. Since the 8th of February, it is the building with the most floors of any other highrise in the world. Little in the way of the curtain wall glass exterior has been installed on the structure, but recent reports indicate that installation of cladding for the Burj Dubai will begin in June 2007.

Burj Dubai's main competitor is being planned at a location only 50 km (31 miles) away from the Burj Dubai site. This tower, Al Burj (originally planned for the center of Palm Jumeirah), is being developed by Nakheel Properties and is also keeping its final height tightly under wraps. It is said to be around 1,200 m (3,937 feet) tall with at least 200 floors, making it a formidable threat to Burj Dubai's status as world's tallest building. Also potentially competing with the Burj Dubai is a proposed 1,001 meter-high (3,284 feet) skyscraper to be erected in Kuwait as part of a new city development project called Madinat al-Hareer ("City of Silk"). However, the project is part of a massive redevelopment expected to take 25 years to complete, according to some reports.[6] The entire development incorporates an Olympic stadium, residences, hotels, and retail facilities.

The tower is designed by Skidmore, Owings and Merrill, who also designed the Sears Tower in Chicago and the Freedom Tower in New York City, among numerous other famous high-rises. The design of Burj Dubai is ostensibly derived from the patterning systems embodied in Islamic architecture. The tower is composed of three elements arranged around a central core. As the tower rises from the flat desert base, setbacks occur at each element in an upward spiraling pattern, decreasing the cross section of the tower as it reaches toward the sky. At the top, the central core emerges and is sculpted to form a finishing spire. A Y-shaped floor plan maximizes views of the Persian Gulf.

The interior will be decorated by Giorgio Armani. An Armani Hotel (the first of its kind) will occupy the lower 37 floors. Floors 45 through 108 will have 700 private apartments on 64 floors (which, according to the developer, sold out within eight hours of going on sale). Corporate offices and suites will fill most of the remaining floors, except for a 123rd floor lobby and 124th floor indoor/outdoor observation deck. The spire will also hold communications equipment. An outdoor zero-entry swimming pool will be located on the 78th floor of the tower. It will also feature the world's fastest elevator, rising and descending at 18 m/s (65 km/h, 40 mph). The world's current fastest elevator is in the Taipei 101 office tower in Taipei, travels at 16.83 m/s (60.6 km/h, 37.5 mph).

The Burj Dubai has been designed to be the centrepiece of a large-scale, mixed-use development that will include 30,000 homes, nine hotels such as the Burj Dubai Lake Hotel & Serviced Apartments, 2.5 hectares (6 acres) of parkland, at least 19 residential towers, the Dubai Mall, and the 12 hectare Burj Dubai Lake. The complete 500 acre development will cost about US $20 billion.

The silvery glass-sheathed concrete building will restore the title of Earth's tallest structure to the Middle East a title not held by the region since Lincoln Cathedral upset the four-millennia reign of Egypt's Great Pyramid of Giza in 1311 AD.

A subtle reference to the onion domes of Islamic architecture can be found in the building's silhouette when looking up at the lobes from near the base.

The tower will be situated on a man-made lake which is designed to wrap around the tower and to provide dramatic views of it.

Engineers working on the design initially considered installing triple-decker elevators, which would have been the first in the world. The final building design calls for double-decker elevators.

The top of the building will contain a public observation deck and a private club above it.

Although the building's shape resembles the bundled tube concept of the Sears Tower, it is structurally very different and is technically not a tube structure.

The design by Skidmore Owings & Merrill replaces a plan to reuse the design for Grollo Tower, which was proposed in Melbourne a few years earlier.

Burj Dubai will become the world's tallest building, along with the world's tallest man-made structure, when it is completed.

The highest residential floor will be at level 109.

An observation deck will occupy the 124th floor.

The building was rotated 120 degrees to allow for less stress from the prevailing winds.

The building sits on a concrete and steel podium with 192 piles descending to a depth of more than 50 meters (164 feet).

A total of 45,000 cubic meters of concrete are used in the foundations with a weight in excess of 110,000 tons.

The exterior cladding is of reflective glazing with aluminum and textured stainless steel spandrel panels with vertical tubular fins of stainless steel.

The cladding system is designed to withstand Dubai's extreme summer temperatures.

Burj Dubai is being built primarily by immigrant engineers and workers from India, Pakistan, Bangladesh, China and the Philippines.