What is the exact time World War 1 ended?

it lasted for 4 years

World War 1 started on July 28, 1914 to 1918

Austria-Hungary, supported by Germany, declared war on Serbia on July 28, 1914. The chain of events that followed in the next few days was as follows:

• Russia, an ally of Serbia, began a partial mobilization.

• Germandy declared war on Russia, August 1, 1914.

• Germany declared war on France, August 3, 1914.

• German troops invaded Belgium, August 4, 1914.

• Britain declared war on Germany, August 4, 1914.