Football Club Internazionale Milano, commonly referred to as Internazionale (pronounced [ˌinternat:sjoˈnaːle]) or simply Inter, and colloquially known as Inter Milan in English-speaking countries, is an Italian professional football club based in Milan, Lombardy. Since 1947, Inter has shared the San Siro stadium with AC Milan—the club from which it originally split. The San Siro is the largest stadium in Italy, with a capacity of 75,817. The long-standing rivalry between the two clubs, known as the Derby della Madonnina, is one of the most widely followed derbies in world football.

Founded in 1908 following a schism within the Milan Foot-Ball and Cricket Club (now AC Milan), Inter won its first championship in 1910. Since its formation, the club has won 37 domestic trophies, including 20 league titles, nine Coppa Italia, and eight Supercoppa Italiana. From 2006 to 2010, the club won five successive league titles, equaling the all-time record at that time. They have won the European Cup/Champions League three times, their latest win in 2010 completed an unprecedented Italian seasonal treble, with Inter winning the Serie A and the Coppa Italia the same year. The club has also won three UEFA Cups, two Intercontinental Cups and one FIFA Club World Cup.

Inter has the highest home game attendance in Italy and the fourth-highest attendance in Europe. Since May 2024, the club has been owned by American asset management company Oaktree Capital Management.