A bar chart showing wars ranked by death toll from 1800-2011, with World War II having the highest number of deaths.

A bar chart titled 'Wars ranked by death toll, 1800-2011' showing horizontal bars representing different wars and their combatant death counts. World War II is at the top with 21.06 million deaths, followed by World War I with 7.11 million. The chart includes wars like Second Sino-Japanese War, Chinese Civil War, Vietnam War, Napoleonic Wars, Korean War, Russian Civil War, Iran-Iraq War, and Spanish Civil War, all with their respective death tolls.

Wars ranked by death toll, 1800–2011 Our World in Data Included are deaths of combatants due to fighting in conventional wars. World War II 21.06 million World War I 7.11 million Second Sino-Japanese War 1.69 million Chinese Civil War 1.2 million Vietnam War 1.06 million Napoleonic Wars 570,328 Korean War 543,936 Russian Civil War 379,483 Iran-Iraq War 228,220 Spanish Civil War 203,839 Data source: Jason Lyall, Project Mars (2020) OurWorldinData.org/war-and-peace | CC BY