Helsinki is the capital, primate and most populous city of Finland. Located on the shore of the Gulf of Finland, it is the seat of the region of Uusimaa in southern Finland, and has a population of 657,674. The city's urban area has a population of 1,268,296, making it by far the most populous urban area in Finland as well as the country's most important center for politics, education, finance, culture, and research; while Tampere in the Pirkanmaa region, located 179 kilometres (111 mi) to the north from Helsinki, is the second largest urban area in Finland. Helsinki is located 80 kilometres (50 mi) north of Tallinn, Estonia, 400 km (250 mi) east of Stockholm, Sweden, and 300 km (190 mi) west of Saint Petersburg, Russia. It has close historical ties with these three cities.

Together with the cities of Espoo, Vantaa, and Kauniainen, and surrounding commuter towns, Helsinki forms the Greater Helsinki metropolitan area, which has a population of over 1.5 million. Often considered to be Finland's only metropolis, it is the world's northernmost metro area with over one million people as well as the northernmost capital of an EU member state. After Stockholm and Oslo, Helsinki is the third largest municipality in the Nordic countries. Finnish and Swedish are both official languages. The city is served by the international Helsinki Airport, located in the neighboring city of Vantaa, with frequent service to many destinations in Europe and Asia.

Helsinki was the World Design Capital for 2012, the venue for the 1952 Summer Olympics, and the host of the 52nd Eurovision Song Contest in 2007.

Helsinki has one of the world's highest urban standards of living. In 2011, the British magazine Monocle ranked Helsinki the world's most liveable city in its liveable cities index. In the Economist Intelligence Unit's 2016 liveability survey, Helsinki was ranked ninth among 140 cities.

The biggest historical museum in Helsinki is the National Museum of Finland, which displays a vast historical collection from prehistoric times to the 21st century. The museum building itself, a national romantic-style neomedieval castle, is a tourist attraction. Another major historical museum is the Helsinki City Museum, which introduces visitors to Helsinki's 500-year history. The University of Helsinki also has many significant museums, including the Helsinki University Museum "Arppeanum" and the Finnish Museum of Natural History.

The Finnish National Gallery consists of three museums: Ateneum Art Museum for classical Finnish art, Sinebrychoff Art Museum for classical European art, and Kiasma Art Museum for modern art, in a building by architect Steven Holl. The old Ateneum, a neo-Renaissance palace from the 19th century, is one of the city's major historical buildings. All three museum buildings are state-owned through Senate Properties.

The city of Helsinki hosts its own art collection in the Helsinki Art Museum (HAM), primarily located in its Tennispalatsi gallery. Pieces outside of Tennispalatsi include about 200 public art pieces and all art held in property owned by the city.

Helsinki Art Museum will in 2020 launch the Helsinki Biennial, which will bring art to maritime Helsinki - in its first year to the island of Vallisaari.

The Design Museum is devoted to the exhibition of both Finnish and foreign design, including industrial design, fashion, and graphic design. Other museums in Helsinki include the Military Museum of Finland, Didrichsen Art Museum, Amos Rex Art Museum, and the Tram Museum.