How much caffeine is in a cup of coffee?
An 8 fl oz cup of brewed coffee has about 96 mg of caffeine, using Mayo Clinic’s reference chart. That is a useful starting point, not a fixed value for every brew. For a larger 12 fl oz serving, the National Coffee Association gives an FDA-based range of 113–247 mg. The coffee, recipe, and size of the drink all matter.
Looking at a label that says 40, 60, or 80 mg? The caffeine comparison chart shows what those amounts look like in brewed coffee and other drinks.
Reference points, not fixed recipes
| Coffee or product | What the evidence supports | How to use the figure |
|---|---|---|
| Regular brewed, non-specialty coffee | The National Coffee Association gives an FDA-based range of 113–247 mg per 12 fl oz. NCA | Treat it as a broad reference point, not as a measured value for every cup or for a particular home recipe. |
| Decaf coffee | The FDA lists 2–15 mg per 8 fluid ounces. FDA | “Decaf” means lower caffeine, not caffeine-free. |
| Espresso | This article does not assign one generic milligram figure to a shot. Published caffeine values vary by coffee type and preparation. review | For a specific drink, use the cafe’s current nutrition information when available. |
| Cold brew, packaged coffee, or retail drinks | A concentrate, a diluted cold brew, and a ready-to-drink product are different finished servings. The FDA notes that product amounts and container sizes can vary. FDA | Compare the caffeine amount with the labelled or stated serving size; do not treat a concentrate as the same thing as a finished drink. |
For a particular packaged beverage, the label or manufacturer’s current nutrition information is the best starting point. Restaurants are not required under U.S. law to disclose caffeine amounts, although the FDA encourages consumers to ask retailers. FDA
Why coffee caffeine varies
A drink name alone does not describe a caffeine amount. The literature review attributes variation within coffee, tea, and infusion categories to factors including the food species examined, cultivation conditions, and the extraction and processing methods used. review of measured caffeine data A coffee recipe also has its own inputs: the coffee used, the coffee-to-water ratio, the water amount, contact time, and the amount served. The 2024 roast study, for example, held a 15:1 water-to-coffee mass ratio and other brewing conditions under control while varying roast and brew time. controlled brew study
That is why a generic “drip,” “espresso,” or “cold brew” figure should not be used to calculate a precise personal total. When the amount matters, identify the finished serving first, then use the product label, a current manufacturer statement, or a cafe’s nutrition information if one is provided. FDA
Roast level is not a dependable caffeine shortcut
Roast labels do not reliably identify a coffee’s caffeine amount. In a controlled 2024 AeroPress study, dark-roast brews generally had lower caffeine concentrations than light- and medium-roast brews under identical brewing conditions. At identical extraction yields, however, dark roasts generally had higher caffeine concentrations. The researchers describe roast-related porosity and soluble-compound changes as competing mechanisms. Lindsey et al., 2024
The useful conclusion is limited: roast degree interacts with extraction and the brewing setup. Choosing light or dark roast is therefore not a dependable way to select a particular caffeine level. For a specific coffee, use serving-specific information rather than a roast label alone. Lindsey et al., 2024
Caffeine and health context
For most adults, the FDA has cited 400 mg a day as an amount not generally associated with negative effects. It is not a universal threshold: the FDA notes wide variation in sensitivity and in how quickly people eliminate caffeine, and it advises considering caffeine from all dietary sources. FDA
For pregnancy, the American College of Obstetricians and Gynecologists states that moderate caffeine consumption of less than 200 mg a day does not cause miscarriage or preterm birth. Its guidance also notes that caffeine can come from tea, chocolate, energy drinks, and soft drinks. ACOG
A scientific review reports an adult caffeine half-life of approximately 3–7 hours and notes that genetic and environmental factors can affect caffeine pharmacokinetics. That range is not a personal timing rule or a basis for a universal daily cutoff. scientific review If you are pregnant, have a health condition, take medication, or have symptoms you think may be related to caffeine, discuss your intake with a qualified clinician. FDA
A practical way to compare drinks
Start with the amount in the finished serving rather than with the brew name. For packaged products, read the declared serving and caffeine information if it is provided. For cafe drinks, ask the retailer when the amount is not published. Add coffee to other caffeine sources instead of treating it in isolation. These steps will usually be more informative than choosing a roast based on a general rule. FDA