1800 in Denmark

Date unknown

• A semaphore line, also known as an optical telegraph, is established between Copenhagen and Schleswig, with 23 reply stations across Zealand, Funen and Als.^[2]
• Kronprinsessegade is established in Copenhagen.^[2]
• Conrad Malte-Brun is sent into exile for his pamphlets which contained outright criticism of the government, something which the new censorship laws forbade.^[2]

January–March

• 14 February – Holger Christian Reedtz, government official, diplomat and landowner (died 1857)
• 2 March – Carl Neergaard, landowner and politician (died 1850)

• 8 March – Johan Laurentz Jensen, painter (died 1856)

April–June

• 2 April – Johannes Dam Hage, editor (died 1857)
• 31 May – Frederik Sødring, painter (died 1862)

July–September

• 2 August – Caspar Peder Rothe Ingerslev, politician 1864)
• 5 September – Gottlieb Bindesbøll, architect (died 1856)

October–December

• 31 October – Peter Lassen, rancher in the United States, namesake of Lassen County, California (died 1859)
• 3 November – Rasmus Carl Stæger, judge, financial advisor to the government, entomologist (died 1875)
• 11 November – Jørgen Balthasar Dalhoff, goldsmith and industrialist (died 1890)
• 4 December – Emil Aarestrup, poet (died 1856)
• 1 December – Charles Ferdinand Léonard Mourier, Supreme Court justice (died 1880)
• 31 December – Carl Heinrich Delcomyn, gunsmith (died 1864)

January–March

• 7 January – Stephan Hofgaard Cordsen, Supreme Court justice (born 1727)

April–June

• 27 April – Christian Jensen Mørup, architect (born 1732)^[3]

October–December

• 7 December – Conrad Holck, courtier and politician (born 1745)

Full date missing

• Anna Klemens, witch trial victim (born 1718)