The caffeine in your cup depends on four things: how much dry coffee went in, how much of it dissolved, the cup size, and the bean itself. Grind and roast get blamed constantly and matter far less than people think. Here are real numbers and where they come from.
The chart
Per-cup figures assume a standard serving for each method. The range is wide because the underlying coffee varies — a dark robusta blend can carry nearly twice the caffeine of a light Arabica at the same dose.
| Method | Serving | Caffeine | Note |
|---|---|---|---|
| Espresso (single) | 30 g | 60–80 mg | Concentrated but small |
| Espresso (double) | 60 g | 120–160 mg | What most cafés serve |
| Drip / filter | 240 ml | 95–165 mg | Highest total per cup |
| V60 / pour over | 240 ml | 90–140 mg | Similar to drip |
| French press | 240 ml | 80–135 mg | Slightly less than drip |
| AeroPress | 220 ml | 70–120 mg | Depends heavily on recipe |
| Moka pot | 60 ml | 110–150 mg | Very high per ml |
| Cold brew | 240 ml | 150–240 mg | Highest of all, usually |
| Instant | 240 ml | 30–90 mg | Highly variable |
Why espresso has less caffeine than drip
A double espresso contains 18 g of coffee. A mug of drip contains 18 to 22 g. Similar dose — so why does espresso feel weaker on paper?
Because caffeine is highly water-soluble and extracts early. Espresso extracts roughly 20% of the bean in 27 seconds; drip extracts 20% over four minutes. The yield of caffeine is comparable, but espresso is served in 36 g of liquid while drip is served in 240 g. The espresso is 6× more concentrated and one-sixth the volume. Total caffeine ends up similar or slightly lower.
What confuses people is the word "strong." Espresso tastes intense and is concentrated, but per serving it often carries less caffeine than a large drip coffee.
| Espresso double | Drip 240 ml | |
|---|---|---|
| Dry coffee | 18 g | 20 g |
| Beverage | 36 g | 240 g |
| Caffeine | 120–160 mg | 95–165 mg |
| Concentration | ~3.9 mg/g | ~0.55 mg/g |
What actually changes the number
Ranked by how much they matter:
- Dose — nearly linear. Double the coffee, double the caffeine, roughly.
- Species — robusta has about twice the caffeine of Arabica. Blends with robusta hit harder than the label suggests.
- Cup size — the variable people ignore. A 470 ml Americano from a café can exceed 200 mg.
- Extraction — under-extracted coffee leaves caffeine in the puck, but the difference is small (caffeine dissolves fast).
- Roast level — nearly irrelevant by weight. Dark beans lose mass in roasting, so a scoop of dark roast weighs less — that's why dark roast sometimes measures lower. Measure by weight and the difference disappears.
Decaf is not zero
Decaf retains 2–15 mg per cup depending on the process and the bean. Swiss Water and CO₂ processes typically land under 10 mg; solvent-based decaf varies more. If you are avoiding caffeine for a medical reason, decaf is not a zero — it is a very low dose.
Daily limits, in cups
Most health authorities put a safe adult intake at 400 mg per day. That is roughly four 240 ml drip coffees, or two and a half large café Americanos. Pregnancy guidance is usually 200 mg.
The practical point: espresso drinkers rarely exceed the limit because the servings are small. Drip and cold brew drinkers exceed it easily because the servings are large and refills are easy. Track the volume, not the number of cups.