Tool

Caffeine in your cup

Estimate the caffeine in an espresso, a filter cup or your own brew, compared with official intake advice.

Estimated caffeine

Estimate only; real cups vary widely. Espressos bought in 20 Glasgow cafés held 51–322 mg each.

Reference lines: EFSA advice for healthy adults (single dose 200 mg; 400 mg a day) and in pregnancy or breastfeeding (200 mg a day). General information, not medical advice.

Dose (g ground coffee)

Midpoint of the 18.1–20.4 g doses in one lab study

Share of the caffeine that reaches the cup (%)

From measured espresso shots

Blend100% arabica

100% robusta100% arabica

Caffeine in roasted arabica (mg/g)

Default: 13 mg/g measured in roasted arabica. Green beans: 9–15 mg/g dry weight

Caffeine in roasted robusta (mg/g)

Default: 22 mg/g, within the 1.2–2.4% reported for green robusta. Green beans: 12–24 mg/g dry weight

Decaf Uses the German legal maximum, 1 mg/g

Keeps your inputs, result and chart. Nothing is stored online.

How it works, the formulas and all sources: Caffeine.