How big is the Tibetan plateau?

Context: Tibet is a region in Asia, covering much of the Tibetan Plateau and spanning about 2,500,000 km2. It is the homeland of the Tibetan people. Also resident on the plateau are some other ethnic groups such as the Monpa, Tamang, Qiang, Sherpa and Lhoba peoples and, since the 20th century, considerable numbers of Han Chinese and Hui settlers. Since the 1951 annexation of Tibet by the People's Republic of China, the entire plateau has been under the administration of the People's Republic of China. Tibet is divided administratively into the Tibet Autonomous Region, and parts of the Qinghai and Sichuan provinces.Tibet is the highest region on Earth, with an average elevation of 4,380 m. Located in the Himalayas, the highest elevation in Tibet is Mount Everest, Earth's highest mountain, rising 8,848.86 m above sea level.

The Tibetan Empire emerged in the 7th century. At its height in the 9th century, the Tibetan Empire extended far beyond the Tibetan Plateau, from the Tarim Basin and Pamirs in the west, to Yunnan and Bengal in the southeast. It then divided into a variety of territories. The bulk of western and central Tibet was often at least nominally unified under a series of Tibetan governments in Lhasa, Shigatse, or nearby locations. The eastern regions of Kham and Amdo often maintained a more decentralized indigenous political structure, being divided among a number of small principalities and tribal groups, while also often falling under Chinese rule; most of this area was eventually annexed into the Chinese provinces of Sichuan and Qinghai. The current borders of Tibet were generally established in the 18th century.

Answer: The Tibetan Plateau spans about 2,500,000 km2