How Fast Is Ketchup Pour?

Ketchup flows at roughly 4 cm per second when poured. As a non-Newtonian fluid, its viscosity drops over 1,000× when shaken — which is why thumping the bottle suddenly works after gentle pouring fails completely.

Ketchup is non-Newtonian — its viscosity drops over 1,000× when shaken or stirred.

• Same pace as a Mars rover driving
• Stirring suddenly thins it 1,000×