How much caffeine is in an espresso?

A standard 30 ml espresso averages 60 to 80 mg of caffeine, with the USDA reference value around 63 mg. Specialty shots, pulled with a heavier 18-20 g dose, commonly land between 100 and 150 mg. That is often less caffeine than a 200 ml filter-coffee mug, which easily carries 150-200 mg.

How much caffeine ends up in your espresso depends on four levers: variety (Arabica or Robusta), ground-coffee dose, water volume pushed through the puck, and extraction time. USDA FoodData Central lists ~63 mg per 30 ml espresso, but that figure assumes the classic Italian 7 g basket. Today's specialty standard, inspired by the SCA, typically runs 18-20 g of coffee for a 36-40 ml double ristretto, which pushes real-world caffeine closer to 100-150 mg per cup.

Variety matters a lot. Green Arabica beans hold 1.2 to 1.5 % caffeine by weight, whereas Robusta sits at 2.2 to 2.7 %. A traditional Italian espresso blending 20-40 % Robusta into Arabica therefore carries more caffeine by construction than a light-roasted Arabica single origin. Roast level, by contrast, barely moves the needle: caffeine is thermally stable up to 235 °C — above typical bean-core temperatures — so the caffeine loss between a light and a dark roast is only around 5 %.

Extraction time has a surprising role. A ristretto cut at 20 ml already pulls 70-80 % of the available caffeine, because caffeine is highly soluble and leaves the puck quickly. A lungo stretched to 60 ml recovers almost all of it (95 %) but mostly harvests extra bitterness. In other words, a lungo holds only 15-20 % more caffeine than a ristretto despite doubling the water — counter-intuitive but confirmed in the EFSA's 2015 Scientific Opinion.

To calibrate: a 33 cl can of Coca-Cola has about 32 mg, a 25 cl Red Bull around 80 mg, a 5-minute black tea 40-70 mg, a traditional 200 ml Belgian filter coffee close to 150 mg. A specialty double espresso pulled in Brussels, Ghent or Antwerp lands near a Red Bull — but concentrated in 40 ml rather than diluted in 250. Families should take note: EFSA advises children and adolescents (under 18) not to exceed 3 mg/kg/day, which already equals ~90 mg for a 30 kg child, reachable in a single double espresso.

Caffeine by drink: USDA/EFSA benchmarks