Toronto ( (listen) tə-RON-toh; locally [təˈɹɒɾ̃ə] or [ˈtɹɒɾ̃ə]) is the capital city of the Canadian province of Ontario. With a recorded population of 2,794,356 in 2021, it is the most populous city in Canada and the fourth most populous city in North America. The city is the anchor of the Golden Horseshoe, an urban agglomeration of 9,765,188 people (as of 2021) surrounding the western end of Lake Ontario, while the Greater Toronto Area proper had a 2021 population of 6,712,341. Toronto is an international centre of business, finance, arts, sports and culture, and is recognized as one of the most multicultural and cosmopolitan cities in the world.

Indigenous peoples have travelled through and inhabited the Toronto area, located on a broad sloping plateau interspersed with rivers, deep ravines, and urban forest, for more than 10,000 years. After the broadly disputed Toronto Purchase, when the Mississauga surrendered the area to the British Crown, the British established the town of York in 1793 and later designated it as the capital of Upper Canada. During the War of 1812, the town was the site of the Battle of York and suffered heavy damage by American troops. York was renamed and incorporated in 1834 as the city of Toronto. It was designated as the capital of the province of Ontario in 1867 during Canadian Confederation. The city proper has since expanded past its original limits through both annexation and amalgamation to its current area of 630.2 km² (243.3 sq mi).

The diverse population of Toronto reflects its current and historical role as an important destination for immigrants to Canada. More than half of residents were born outside of Canada, more than half of residents belong to a visible minority group, and over 200 distinct ethnic origins are represented among its inhabitants. While the majority of Torontonians speak English as their primary language, over 160 languages are spoken in the city. The mayor of Toronto is elected by direct popular vote to serve as the chief executive of the city. The Toronto City Council is a unicameral legislative body, comprising 25 councillors since the 2018 municipal election, representing geographical wards throughout the city.

Toronto is a prominent centre for music, theatre, motion picture production, and television production, and is home to the headquarters of Canada's major national broadcast networks and media outlets. Its varied cultural institutions, which include numerous museums and galleries, festivals and public events, entertainment districts, national historic sites, and sports activities, attract over 43 million tourists each year. Toronto is known for its many skyscrapers and high-rise buildings, in particular the tallest free-standing structure on land outside of Asia, the CN Tower.

The city is home to the Toronto Stock Exchange, the headquarters of Canada's five largest banks, and the headquarters of many large Canadian and multinational corporations. Its economy is highly diversified with strengths in technology, design, financial services, life sciences, education, arts, fashion, aerospace, environmental innovation, food services, and tourism. Toronto is the third-largest tech hub in North America after Silicon Valley and New York City, and the fastest growing.