Emporis
Emporis, a company keeps statistics on construction projects and finished
Seven of the 10 are being built in China, including the Shanghai Tower, which has just topped out at 2,073.49 feet to become the world's second-tallest building.
But the tallest of them all will be the Kingdom Tower, which is currently being erected in Jeddah, Saudi Arabia and is expected to be finished by 2018. If it is completed as planned, it will become the world's tallest building at a staggering 3,280.84 feet.