The Dallas–Fort Worth metroplex, officially designated Dallas–Fort Worth–Arlington by the U.S. Office of Management and Budget, is the most populous metropolitan statistical area in the U.S. state of Texas and the Southern U.S., encompassing 11 counties. Its historically dominant core cities are Dallas and Fort Worth. It is the economic and cultural hub of North Texas. Residents of the area also refer to it as DFW (the code for Dallas Fort Worth International Airport) or the Metroplex. The Dallas–Fort Worth–Arlington metropolitan statistical area's population was 7,637,387 according to the U.S. Census Bureau's 2020 census, making it the fourth-largest metropolitan area in the U.S. and the eleventh-largest in the Americas. In 2016, the Dallas–Fort Worth metroplex had the highest annual population growth in the United States. By 2023, the U.S. Census Bureau estimated that the Dallas-Fort Worth metropolitan area's population had increased to 8,100,037, with the highest numerical growth of any metropolitan area in the United States. By 2025, NCTCOG estimated that the Dallas-Fort Worth metropolitan area's population had increased to around 8,578,654 million residents, making the Dallas-Fort Worth metropolitan area around 1.42 million residents from becoming a megacity.

The metropolitan region's economy, also referred to as Silicon Prairie, is primarily based on banking, commerce, insurance, telecommunications, technology, energy, healthcare, medical research, transportation, manufacturing, and logistics. As of 2022, Dallas–Fort Worth is home to 23 Fortune 500 companies, the 4th-largest concentration of Fortune 500 companies in the United States behind New York City (62), Chicago (35), and Houston (24). In 2016, the metropolitan economy surpassed Houston, the second largest metro area in Texas, to become the fourth-largest in the U.S. The Dallas–Fort Worth metroplex boasted a GDP of just over $620.6 billion in 2020 (although both metropolitan regions have switched places multiple times since GDP began recording). If the Metroplex were a sovereign state, it would have the twentieth largest economy in the world as of 2019. In 2015, the conurbated metropolitan area would rank the ninth-largest economy if it were a U.S. state. In 2020, Dallas–Fort Worth was recognized as the 36th best metropolitan area for STEM professionals in the U.S.

The Dallas–Fort Worth metroplex comprises the highest concentration of colleges and universities in Texas. The UT Southwestern Medical Center is home to six Nobel Laureates and was ranked No. 1 in the world among healthcare institutions in biomedical sciences. The Metroplex is also the second most popular metropolis for megachurches in Texas (trailing the Greater Houston metropolitan area), ranked the largest Christian metropolitan statistical area in the U.S., and has one of the largest LGBT communities in Texas since 2005.

A portmanteau of metropolis and complex, the term metroplex is credited to Harve Chapman, an executive vice president with Dallas-based Tracy-Locke, one of three advertising agencies that worked with the North Texas Commission on strategies to market the region. The NTC copyrighted the term "Southwest Metroplex" in 1972 as a replacement for the previously-ubiquitous "North Texas", which studies had shown lacked identifiability outside the state. In fact, only 38 percent of a survey group identified Dallas and Fort Worth as part of "North Texas", with the Texas Panhandle also a perceived correct answer, being the northernmost region of Texas.

The United States Census Bureau determined the Metroplex encompasses 9,286 square miles (24,100 km²) of total area; 8,991 sq mi (23,290 km²) is land, and 295 sq mi (760 km²) is covered by water. The conurbated metropolitan area is larger in area than the U.S. states of Rhode Island and Connecticut combined, and larger than New Jersey. If the metropolitan area were a sovereign state, it would rank the 162nd largest state by total area after Lebanon. The U.S. Office of Management and Budget combines the Dallas–Fort Worth metroplex with the Sherman–Denison metropolitan area and seven micropolitan statistical areas to form the Dallas–Fort Worth TX–OK combined statistical area.

The Dallas–Fort Worth metroplex overlooks mostly prairie land with a few rolling hills dotted by human-made lakes cut by streams, creeks and rivers surrounded by forested land. The Dallas–Fort Worth metroplex is situated in the Texas blackland prairies region, so named for its fertile black soil found especially in the rural areas of Collin, Dallas, Ellis, Hunt, Kaufman, and Rockwall counties.

Many areas of Denton, Johnson, Parker, Tarrant, and Wise counties are located in the Fort Worth Prairie region of North Texas, which has less fertile and more rocky soil than that of the Texas blackland prairie; most of the rural land on the Fort Worth Prairie is ranch land. A large onshore natural gas field, the Barnett Shale, lies underneath this area; Denton, Tarrant and Wise counties feature many natural gas wells. Continuing land use change results in scattered crop fields surrounded by residential or commercial development. South of Dallas/Fort Worth is a line of rugged hills that goes north to south about 15 miles (24 km) that looks similar to the Texas Hill Country 200 miles (320 km) to the south.

The Dallas–Fort Worth–Arlington metropolitan statistical area is formed by a combination of two separate metropolitan statistical divisions. The Dallas–Plano–Irving MDA and Fort Worth–Arlington–Grapevine MDA come together to form one full metropolitan area or conurbation.