The Copenhagen Metro (Danish: Københavns Metro [kʰøpm̩ˈhɑwˀns ˈme̝ːtsʰʁo]) is a light rapid transit system in Copenhagen, Denmark, serving the municipalities of Copenhagen, Frederiksberg, Tårnby, and Dragør.

First opened in October 2002, the driverless light metro supplements the larger S-train rapid transit system, and is integrated with local DSB and regional (Øresundståg) trains and municipal Movia buses. The metro operates 4 lines and operates 44 stations, 30 of which are underground. The M1 and M2 lines serve western and eastern Amager (including Copenhagen Airport) respectively, sharing a common line between the city centre and Vanløse. The M3 is a wholly underground circular line connecting Copenhagen Central Station with Vesterbro, Frederiksberg, Nørrebro, Østerbro and Indre By. The most recent line, M4, supplements the M3 line and connects it to Nordhavn and Sydhavn, as well as Valby via Copenhagen South. The fifth line, M5, is currently in the planning stages and will serve Refshaleøen as well as the under-construction Lynetteholmen neighbourhood, with an expected opening date in 2035.

In 2023, the metro carried 120 million passengers. Along with the New York City Subway and Chicago "L", the Copenhagen Metro is one of three rapid transit systems in the world to operate 24/7 throughout their city limits.

The system is owned by Metroselskabet (The Metro Company), which is owned by the municipalities of Copenhagen and Frederiksberg, and the Ministry of Transport. The M1 and M2 use 34 trains of the Hitachi Rail Italy Driverless Metro class and stationed at the Control and Maintenance Center at Vestamager. The trains are 2.65 m (8 ft 8 in) wide and three cars long; their 630 kW (840 hp) power output is supplied by a 750-volt third rail. The metro trains were originally planned to be four cars long, but trains were reduced to three cars per set as a savings measure. Platforms are – although shorter than originally planned – built to accommodate trains with four cars, and the automatic doors can be modified accordingly should the need arise.

Operation of the system is subcontracted to a private company. For the history of service, this has been Metro Service A/S. Trains run continually, twenty-four hours a day, with the headway varying from two to four minutes in daytime, with longer intervals (up to twenty minutes) during the night.^{[citation needed]}

Planning of the Metro started in 1992 as part of the redevelopment plans for Ørestad with construction starting in 1996, and stage 1, from Nørreport to Vestamager and Lergravsparken, opened in 2002. Stage 2, from Nørreport to Vanløse, opened in 2003, followed by stage 3, from Lergravsparken to Lufthavnen, in 2007.^{[citation needed]}

The City Circle Line (Danish: Cityringen) is an entirely underground 15.5 km (9.6 mi) loop through central Copenhagen and Frederiksberg with 17 stops. It does not share any track with the M1 and M2 lines, but intersect them at Kongens Nytorv and Frederiksberg stations. Before the Cityringen opened, the Metro expected that it would cause its ridership should almost double from its 2016 levels to 116 million annual passengers.

A fourth line, M4, operates as an extension of the M3 to Nordhavn and Sydhavn. The first stationed opened in Nordhavn in March 2020, and the five-stop, 4.5 km (2.8 mi), extension to Sydhavn opened in 2024. The M4 terminates at Copenhagen South Station and serves as another metro connection to the S-train network, regional trains, and long-distance trains on the current lines and the high speed Copenhagen-Ringsted railway. The Copenhagen Metro is expected by Metroselskabet to triple the ridership from its current level of 200,000 per weekday to 600,000 per weekday by 2030.