Tool
Caffeine estimator
A range, never a number, from dose, method and serving size — with the things that widen the range stated plainly.
Estimated: 80-101mg caffeine
Estimated from dose, brew method and serving size — not a measurement of this specific cup. Species was not specified, so this uses a general estimate that does not account for arabica/robusta differences.
This is a rough estimate, not a measurement — actual caffeine content varies by bean, roast batch and extraction. It is not medical guidance and should not be used to judge suitability for pregnancy, medication use or any health condition. See the caffeine methodology.
How it works
Caffeine extracted is estimated as the dose multiplied by a per-method milligrams-per-gram range, then shared across the brewed volume and sampled by your serving. The coefficient ranges come from published figures and are wide because the underlying variation is wide: bean, roast batch, species and extraction all move it.
What the inputs mean
- Total brewed volume
- Everything the dose was brewed into — the whole pot, not the cup you are drinking, if you brewed a batch.
- Serving
- How much of that you are actually drinking.
- Species
- Robusta is commonly reported as carrying more caffeine than arabica. Most specialty coffee is arabica; most supermarket blends contain some robusta and rarely say how much.
Worked examples
A double espresso
- Dose 18 g
- Yield 36 ml
- Serving 36 ml
- Arabica
Result: Roughly 59-79 mg — a range, not a figure.
Common mistakes
Reading the midpoint as the answer
The width of the range is the finding. A cup could genuinely be at either end.
Assuming a darker roast means less caffeine
Roast level changes caffeine much less than most people expect. Dose and species matter far more.
Comparing an espresso to a mug of filter by concentration
Espresso is far more concentrated and far smaller. Per serving, a mug of filter usually carries more.
What the result does not mean
- This is an estimate from a general model, not a measurement of your cup. Nothing here has been laboratory-tested.
- It is not medical guidance, and it must not be used to assess safety for pregnancy, medication or any health condition.
What this does not account for
- Always shows a range, never a single number — actual caffeine content varies by bean, roast batch and extraction, not just the inputs below.
- The per-method coefficients are calibrated against the per-drink figures already published in CoffeeHQ's catalogue rather than invented independently.
- This is not medical guidance and should not be used to judge suitability for pregnancy, medication use or any health condition.