Coffee Caffeine Calculator
Not all coffee is created equal. Whether it's a concentrated espresso shot or a large cold brew, calculate exactly how much caffeine you're consuming.
The type of coffee or beverage
The volume of the drink
Custom concentration if not using presets
How much caffeine is too much for an average adult?
The FDA and most health organizations suggest a limit of approximately 400 milligrams of caffeine per day for healthy adults. Exceeding this amount can lead to jitteriness, insomnia, increased heart rate, and anxiety. However, caffeine sensitivity varies wildly between individuals.
How long does caffeine stay in your system?
Caffeine has a "half-life" of about 5 to 6 hours for the average adult. This means if you consume 200mg of caffeine at noon, you will still have roughly 100mg in your bloodstream by 6pm. This is why late-afternoon coffee often interferes with sleep quality, even if you don't "feel" the buzz.
Does decaf coffee still contain caffeine?
Yes. Decaffeination is not a 100% removal process. A typical cup of decaf coffee contains roughly 2 to 15 milligrams of caffeine, compared to 95-150mg in a regular cup. While negligible for most, people with extreme sensitivity should still be aware.
How does the caffeine content vary between brew methods?
Caffeine content is primarily determined by the amount of coffee beans used and the extraction time. Espresso has a higher concentration per ounce, but because the serving size is so small, a double shot of espresso often has similar caffeine to a 12oz drip coffee. Cold brew typically has the highest caffeine content because it uses a higher coffee-to-water ratio and a longer steep time.