Question: how much caffeine in a single coffee bean?
Answer: But how much caffeine is in a coffee bean? On average, a single arabica coffee bean contains 1.9 milligrams of caffeine (1.2 – 1.5g of caffeine per 100g). A single robusta coffee bean has 2.9 milligrams of caffeine (2.2 – 2.7g of caffeine per 100g).