⚡ Caffeine Content Estimator
Select a coffee type and serving size to see a general estimate of caffeine content, based on commonly published averages. Actual caffeine varies by bean, roast, and brew method.
The figures behind the estimate
Each drink type carries a fixed milligrams-per-ounce average, and the tool simply multiplies:
caffeine (mg) = mg per fl oz × serving (fl oz)| Type | mg per fl oz | Typical serving |
|---|---|---|
| Espresso | 40 | 1 oz shot = 40 mg |
| Drip coffee | 15 | 8 oz cup = 120 mg |
| Cold brew | 12 | 12 oz glass = 144 mg |
| Instant | 8 | 8 oz cup = 64 mg |
| Decaf | 0.4 | 8 oz cup = 3 mg |
Servings run from 1 to 20 fl oz. For espresso, enter the volume of the shot - 1 oz for a single, 2 oz for a double - not the size of the latte it goes into. Typing 8 with espresso selected gives 320 mg, which is eight ounces of neat espresso rather than a milk drink.
Why these are estimates, not measurements
Caffeine in a real cup swings by a factor of two or three either way. Robusta beans carry roughly double the caffeine of arabica. Dose matters more than roast: a 22 g pour over yields far more than a 12 g one at the same volume, and cold brew concentrate is several times stronger than the same drink after dilution. Testing of one chain's medium drip has found anywhere from 100 mg to over 250 mg. Treat the number here as a ballpark, not a dose.
Frequently asked questions
How much caffeine is in a cup of coffee?
Around 120 mg for an 8 fl oz drip coffee on these averages. Published ranges for the same cup run from 70 mg to 140 mg depending on bean and dose.
Does espresso have more caffeine than drip coffee?
Per ounce, yes - 40 mg against 15 mg. Per drink, no. A 1 oz shot is about 40 mg while an 8 oz drip coffee is about 120 mg, so the mug wins comfortably.
How much caffeine per day is too much?
Health agencies in the US and EU put 400 mg a day as the level most healthy adults tolerate, which is roughly three 8 oz drip coffees. Lower limits apply in pregnancy, usually around 200 mg.