Dubai (, doo-BY; Arabic: دبي, romanized: Dubayy, IPA: [dʊˈbajj], Gulf Arabic pronunciation: [dəˈbaj]) is the most populous city in the United Arab Emirates (UAE) and the capital of the Emirate of Dubai, the most populated of the 7 emirates of the United Arab Emirates. Established in the 18th century as a small fishing village, the city grew rapidly in the early 21st century with a focus on tourism and luxury, having the second most five-star hotels in the world, and the tallest building in the world, the Burj Khalifa, which is 828 metres (2,717 ft) tall.

In the eastern Arabian Peninsula on the coast of the Persian Gulf, it is also a major global transport hub for passengers and cargo. Oil revenue helped accelerate the development of the city, which was already a major mercantile hub. A centre for regional and international trade since the early 20th century, Dubai's economy relies on revenues from trade, tourism, aviation, real estate, and financial services. Oil production contributed less than 1 percent of the emirate's GDP in 2018. The city has a population of around 3.49 million (as of 2021).