How much caffeine is in coffee?
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Ever wondered, "How much caffeine is in my coffee?" Maybe your system can’t take it. Maybe you want some extra umph. Either way, you're not alone – it’s actually one of the most asked coffee questions on Google. The answer isn't straightforward, as caffeine content can vary significantly for drink to drink.
In this guide, we'll explore the 3 main factors affecting caffeine levels in your cup and we’ll debunk a common myth along the way.
Factor 1: Coffee Variety Matters
Coffee comes in two main varieties: Arabica and Robusta. Arabica, which accounts for about 75% of global coffee consumption (Trade), generally has less caffeine than Robusta. In the US, it’s likely you’re drinking mostly Arabica, but you may not be. Many high-caffeine brands like Deathwish and brands from origins like Vietnam (Nguyen Coffee, for example) use in Robusta beans for it’s bolder flavor and bigger caffeine kick. Heck, even Blue Bottle is in on the game.
Here's how Arabica and Robusta stack up in terms of caffeine content:
Arabica: 0.9-1.9% of unroasted weight
Robusta: 1.2-2.4% of unroasted weight
You can see how much of a difference there can end up being even if you’re drinking 1 or 2 cups. Imagine you’re used to a less-caffeinated Arabica and you go to a friend’s house an drink a 2.4% Robusta. You may find yourself in a precarious place.
Fun fact: one time I was at Heine Brothers in Louisville and thought I was having a heart attack — turns out it was a caffeine induced panic attack. I think I had four coffees and no breakfast before 12. Cool.
Factor 2: Roast Level and the Dark Roast Myth
Roast level has an impact, but it’s not why most people think. Contrary to popular belief, dark roast doesn't necessarily mean more caffeine on a per bean basis. Here's the truth:
Light, medium, and dark roasts have similar caffeine content by weight
Darker roasts lose more mass during roasting and therefore weigh less than lighter roasts
If dark roast weighs less, you’ll need more beans overall in your brew — and more beans means more caffeine
To illustrate it more concretely, take this example given in the article, “A Bit About Caffeine” by Mark Prince. Mark did the calculations and found that for 35 grams of ground coffee across roast levels there was the following amounts of caffeine:
Light Roast: 490mg caffeine
Medium Roast: 520mg caffeine
Dark Roast: 600mg caffeine
This shows up to 22% more caffeine in dark roast compared to light when measured by volume.
So is dark roast “stronger” than other types of coffee? Yes, when the volume of water and weight of coffee is held equal — a cup of dark roast is in fact stronger in caffeine content, not to mention the flavor profile.
Factor 3: Brewing Method or Style Impacts Caffeine Extraction
Different brewing methods extract caffeine differently due to variations in:
Brewing time - how long the coffee is immersed in water
Grind size - the smaller the size, the more soluble material can be extracted (that’s why espresso is so fine and quick)
Water temperature - water can affect how quickly caffeine is extracted
Coffee-to-water ratio - more water means a more diluted coffee and that means less caffeine by liquid volume
Let's compare some popular brewing methods
8oz of drip coffee contains approximately 95mg caffeine (USDA).
Cold brew is generally higher in caffeine due to longer extraction times. I couldn’t find an average but I did see where Stumptown's 10.5 oz ready-to-drink Stubbies (my first real foray into cold brew) have 257mg caffeine. Starbucks lists its grande (16 ounce) cold brew as having 205mg caffeine.
Espresso, universally known as a “strong” drink, contains 64mg of caffeine per ounce (30g). So if you’re having a double shot latte you’d be having 128mg of caffeine.
By the way…
If you want to control your brewing time, grind size, water temperature, and coffee-to-water ratio, check out my favorite coffee tools.
The zeroHero Mini Espresso Scale (Buy it here)
Fellow Stagg Kettle with variable temperature adjustment (Buy it here)
zeroHero hand grinder (Buy it here) or Fellow Opus (Buy it here)
Conclusion
There’s no universal standard for caffeine in coffee. It really just depends on what you drink. But if you have a sense of how much caffeine is in a given drink you can be more aware of your total intake. Remember, individual sensitivity to caffeine varies, so pay attention to how your body responds.
Until next time... Peace. ✌️
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