Caffeine In Coffee – The Complete Guide [2021 Update]
We all know caffeine as the component in coffee that wakes us up. But some people drink two, three, or four cups in a day without giving much thought to how much caffeine is in a coffee, let alone what amount of it is safe to consume.
Caffeine can have many benefits when used correctly. But like all drugs, it can become hazardous to your health when taken in excess.
What is Caffeine?
Caffeine is a bitter white powder in its purest form. And it is consumed in some way by an estimated 90 percent of people around the world each day.
That makes caffeine the world’s most widely used psychoactive drug. And to fully utilize this substance, it’s essential to understand what it is and what it does.
Where Does Caffeine Come From?
Caffeine can be found in around 60 plant species all in all. Coffee beans, tea leaves, and cocoa are some of the most common natural sources of caffeine. Among these, coffee has the highest caffeine content.
Large beverage companies also synthetically produce caffeine. This type of caffeine is what adds the “energy” in energy drinks. It is also used to complement sweetness in soft drinks, or as a caffeine supplement in pill form.
What Does It Do?
Caffeine works its magic on the central nervous system. It gives the feeling of being awake, alert, and less tired when it stimulates the brain. But there is such a thing as overstimulation.
Being awake, alert, and less tired, can turn into insomnia, anxiety, and eventual fatigue if you consume caffeine recklessly.
Is Caffeine Addictive?
You can develop a physical and psychological dependence on caffeine. And this is especially true for people who consume it in high doses.
But, caffeine isn’t as addictive by the same magnitude as other stimulants. You may experience withdrawal symptoms after suddenly not being able to drink your daily serving of coffee. These symptoms, however, are considered mild and transient.
How much caffeine is in coffee?
Above are the illustrated approximate figures for the caffeine content in the types of coffee people are most familiar with. You can also see them below:
- Espresso (1 oz): 126 mg / 126 mg/oz
- Espresso, decaffeinated (1 oz): 7.5 mg / 7.5 mg/oz
- Drip coffee (8 oz): 145 mg / 18.1 mg/oz
- Drip coffee, decaffeinated (8 oz): 6.2 mg 0.8 mg/oz
- Instant coffee (8 oz): 57 mg / 7.1 mg/oz
- Instant coffee, decaffeinated (8 oz): 2.8 mg / 0.4 mg/oz
A high caffeine concentration gives the espresso its strong, bitter taste. Its strength in taste is just as strong as its punch. But a serving of drip/brewed coffee has more caffeine in total than espresso due to the serving (not many people really drink 1 oz of coffee through a shot alone ).
It is worth noting that decaf coffee does not necessarily mean there’s zero caffeine in a coffee, its typically less than 3% though. Even then, it’s still not a good idea to drink absurd amounts in one day. But, just one serving is not enough to cause alarm if you’re caffeine sensitive.
To learn more about decaf, check out our post on the process to make decaffeinated coffee.
As you can probably tell, the question of how much caffeine in a coffee results in an ambiguous answer and that it depends on your cup size and brew type!
Other Popular Brewing Methods
As you well know, the list above is just the tip of the iceberg. When it comes to the ways you can enjoy your caffeine, there’s way more than just these three.
Here are some other popular coffee brewing methods for getting your caffeine fix:
- Moka pot
- Pour over
- Cold brew
- French press
All these methods result in different taste profiles and different levels of caffeine.
Why Does the Amount of Caffeine Vary in Each Cup?
The amount of caffeine in your cup of coffee is dependent mostly on three factors. These are your beans, your coffee to water ratio, and your brewing method of choice.
The first and most obvious factor that will determine how much caffeine in coffee is is your coffee bean. Not just which you brew with, but also how you brew it.
There are dozens of varieties of coffee, but two main species used for your everyday cup of coffee are arabica and robusta.
Arabica is the more popular variety of the two. It accounts for more than 60% of the world’s coffee production. It is grown in higher altitudes and tends to have a sweet and mild taste.
Robusta is grown in lowland areas and tends to have a stronger and more bitter taste than arabica. Vietnam and Indonesia are two notable countries that prefer robusta over arabica.
The reason for robusta’s bitter taste is its caffeine level. It has twice the amount of its arabica counterpart. The bitterness of caffeine also acts as an insect repellant. Since there are more insects in lowland areas, robusta coffee contains more of it than arabica as a survival mechanism.
Light Roast vs. Dark Roast: Which Has More Caffeine?
A light roasted bean has the same amount of caffeine as a dark roasted bean of the same variety. But, a cup of light roasted coffee contains less caffeine than a cup of dark roasted coffee on average.
Allow me to explain what that means.
The only difference in making a light roast and a dark roast is that dark roasted coffee is roasted for a longer duration.
But it’s roasting temperature, not roasting time, that can cause a significant decrease in the amount of caffeine in coffee.
What sort of temperature increase would you need to have for this to happen? The normal roasting temperature is around 470F, but at around 600oF, you start losing the caffeine in coffee.
This means that one dark roasted bean will have the same amount of caffeine as a light roasted bean when roasted at average temperatures.
But even though the bean does not lose caffeine throughout the roasting process, what it does lose is water. This means that at the end of a roast, a dark roasted bean will weigh less than a light roasted bean. So a hundred grams of dark roasted coffee will contain more individual beans than a hundred grams of light roasted coffee.
Because of this, the hundred grams of dark roasted coffee will contain more caffeine than the hundred grams of light roasted coffee.
Again, a dark roasted bean has the same caffeine content as a light roasted bean. But because the bean loses weight throughout the roasting process. So, a serving of dark roasted coffee will contain more caffeine than an equal serving of light roasted coffee!
Another thing to consider in terms of manipulating caffeine levels is grind size.
A finer grind size will result in a larger total surface area of the grind. This means that your water will have more coffee to extract caffeine from. So the finer your ground coffee is, the more caffeine you will be able to obtain from it.
But this doesn’t mean your grind size should be as fine as possible all the time. For methods that have longer extraction times and lower water temperatures, a coarser grind size is recommended. This is to ensure that the resulting cup of coffee isn’t bitter. For example, for optimal results, use a grinder suitable for the french press as this will output coarse grounds.
Moka pot and french press are examples of brewing methods that require a coarser grind.
Coffee To Water Ratio
“How much coffee did you put in?” This is another factor that affects how much caffeine is present in a cup of coffee.
The ratio between how much ground coffee you’re using and how much water you’re brewing with determines the amount of caffeine in your cup of coffee. All other variables being equal, the greater the ratio of ground coffee to water, the more caffeine will be present in your drink.
Lastly, your brewing technique of choice also affects how much caffeine you can extract from your coffee. We discussed this when I listed the amount of caffeine present in one serving of a cup of joe extracted using various brewing methods.
Apart from grind size, different methods require different extraction times and water temperatures.
Generally, the higher the water temperature is, the more efficiently you will be able to extract caffeine. This is the case for the espresso and Moka pot methods of brewing coffee. Extraction time for these methods is much faster than if you’re extracting at lower water temperatures.
To illustrate what I mean, here’s how much caffeine there is in one serving of each of the popular brewing methods I listed above. The same type of coffee bean was used for all methods.
- Espresso (1 oz) – 126 mg / 126 mg/oz
- Moka Pot (1 oz) – 69 mg / 69 mg/oz
- Pour Over (8 oz) – 173 mg / 21.6 mg/oz
- Cold Brew (4 oz) – 268 mg / 67 mg/oz
- French Press (8 oz) – 162mg / 20.3 mg/oz
The type of brewing method has a significant effect on how much caffeine is in your coffee. You can see this in the amount of caffeine per fluid ounce.
But it’s important to note that these are just sample values for caffeine levels. If drip coffee is too strong for you, you might opt to drink only 4 oz per serving instead of 8. Or you may want to drink 2 oz of moka pot coffee instead of 1.
The reality is that no two people will like their coffee exactly the same way. But there are general preferences that exist in every country when it comes to enjoying a cup of coffee.
Caffeine Depending on Where You’re From
People all around the world are used to different levels of caffeine in their everyday cup of coffee. And how a country likes to take their caffeine says quite a bit about their culture.
- Preferred method: Drip
- Preferred bean variety: Arabica
Drip coffee is especially popular in diner culture, where customers come for the food first and coffee second. Although drip coffee is not the best way to get the best flavor out of your coffee, it does contain a large amount of caffeine per serving and can brew big batches with minimal effort.
No wonder drip coffee is served pretty much everywhere you go as the primary source of caffeine!
- Preferred method: Phin
- Preferred bean variety: Robusta
Phin coffee is somewhat of a cross between a drip coffee maker and a pour over. And pretty much every coffee shop and household in Vietnam has one.
It only serves one cup of coffee but takes several minutes to make. Unlike in the U.S, consuming a daily dose of caffeine is considered a leisure activity in Vietnam. They don’t rush to make their brew, and it’s evident in how much they enjoy coffee. On every street you will see coffee shops full of people enjoying a cup.
However, their beans of choice are robusta beans, as Vietnam happens to be the number one producer of robusta in the world. The combination of a Phin and robusta results in a cup of coffee that contains a lot of caffeine.
As a result, coffee in Vietnam can taste quite bitter, and on its own is too bitter for most folks.
This is why it’s common in Vietnam to add condensed milk to coffee for a creamy sweet drink, often drunk cold with ice.
- Preferred method: Espresso
- Preferred bean variety: Arabica
In Europe, Italians use mostly arabica beans, and the espresso is their preferred way of drinking coffee. After all, Italy is the birthplace of the espresso machine, and home of some of the best coffee in the world!
Their appreciation for the art of making coffee is the reason why Italians like their coffee strong-tasting and full of flavor.
Espresso machines can be found in just about all artisanal coffee shops in the world. And you’ll find that it’s more often than not also a coffee shop’s most used piece of equipment.
What Makes The Espresso Special
Espresso is prepared by pushing 1 oz of hot water through tightly packed ground coffee under high pressure (at least 9 bar, often 15+) for under a minute. The result is a strong coffee drink with a high caffeine concentration, a complex flavor profile, and a thick, velvety texture.
This makes it the most versatile of all the brewing methods. If you’ve seen a coffee shop menu, you know it can be enjoyed in a variety of ways. There can be so much variety, in fact, that it might be hard to tell the difference between them all.
One way to enjoy espresso is on its own. But the extraction time and resulting change in volume results in different variations. These drinks have varying amounts of caffeine and different names.
A doppio is a double shot of espresso, as doppio means “double” in Italian.
The only difference between a doppio and a single shot of espresso is their volume, meaning a doppio contains twice the amount of caffeine of a single shot as well. This double shot is what baristas use in making various types of coffee drinks.
Lungo means “long” in Italian, so this has the same amount of coffee but is pulled longer than a single shot. Though the extraction time is longer, it doesn’t have much more caffeine than a single shot, as the main difference is the amount of water.
So it is weaker in terms of taste than a single shot, making it an option for people who enjoy strong-tasting coffee but find the flavor in a standard single shot too strong.
Although ristretto means “limited” in Italian, don’t make the mistake of thinking it is a mild version of the single shot espresso.
The reason for its name is that a ristretto has half the amount of water of a single shot, but the same amount of coffee. This is achieved by pulling shorter, or in other words, shortening the extraction time.
The result is a more concentrated shot, with a thicker texture, more flavor, and just a little less caffeine than a single shot.
Milky Espresso Drinks
There aren’t as many people who enjoy taking shots as there are who enjoy them with milk. So these milky variations are probably what you drink more often.
The latte, cappuccino, and flat white all fall under this category, with the difference being the amount of milk and foam in each drink. But the caffeine levels in these drinks entirely depend on the quantity of espresso used in their preparation.
Other Caffeine-Based Drinks
No matter how well-prepared a cup of coffee is, there are people who just don’t find it to be a pleasurable experience.
It’s always either too bitter, too strong, or just not sweet enough. But these people still need their caffeine fix. And for that, they turn to other caffeinated beverages.
Popular Energy Drinks
One alternative for caffeine is an energy drink. Although the concentration in these drinks is less than that in a cup of joe, there is much caffeine present per drink due to their serving sizes.
Monster Energy Drink and Rockstar Energy Drink are two of the most popular options. They contain only 10 mg of caffeine per oz, but they come in 16-oz containers, resulting in 160 mg of caffeine per serving. That’s more caffeine than most single servings of coffee.
Another source of caffeine people turn to is soda, but there isn’t enough caffeine to feel a significant effect. One well-known soda that contains caffeine is Coca-Cola.
However, with the caffeine only being at 34 mg per serving, it’s rather weak when compared to an energy drink or a cup of joe. Although, it does send your blood sugar spiking, which isn’t a good thing!
The reason soda manufacturers add caffeine to drinks is to make the flavor more complex. It complements the sweetness of their beverages as well.
Caffeine comes in many shapes and forms. Ultimately, people consume it when they need to wake up and stay up. Every once in a while, an individual consumes an ungodly amount of caffeine to finish a ridiculous amount of work. But the overconsumption of caffeine can have unpleasant and even life-threatening side effects.
What are the Effects of Caffeine on Your Body?
Caffeine wakes you up by binding itself to the adenosine receptors in your brain. It’s able to do this because caffeine has a similar structure to that of adenosine.
Adenosine is a chemical that induces the feeling of being tired or drowsy, or in other words, slowing down, while caffeine does the exact opposite.
The brain then inhibits the effects of the compound, and Instead of slowing down, the nerve cells in the brain start to fire signals rapidly due to caffeine uptake.
Instead of slowing down, the nerve cells in the brain increase their momentum. So your pituitary gland lends you a hand by releasing epinephrine. You and I know this better as adrenaline.
In emergency situations, adrenaline is your friend. It dilates your pupils, increases your heartbeat, and facilitates the release of sugar to your liver to give you energy. When it comes to coffee, it’s the rush you feel from a cup!
The Benefits of Caffeine
Most people are familiar with how caffeine helps us in our day-to-day.
The adrenaline in our system gives you additional energy and makes you more capable of mental and physical tasks.
Caffeine essentially arms you with the energy and focus on taking on whatever task lies before you. But that’s not all your daily cup of coffee is good for.
Cognitive Function and Mental Health
Aside from making you focused and alert, a moderate amount of caffeine has been shown to increase memory in people who use it every day. It also improves reaction time and logical reasoning in individuals who are sleep deprived.
Coffee is an especially good source of caffeine. This is because it contains polyphenols that protect the brain against memory loss, and this study claims that it may reduce the risk of Alzheimer’s disease.
Caffeine also stimulates the production of serotonin, which regulates mood, anger, and aggression. An analysis of 12 different studies concluded that moderate intake could lower the risk of depression.
A study in the Journal of Applied Physiology shows that athletes who consumed caffeine along with carbohydrates after a hard workout had 66% more glycogen in their muscles than athletes who ate just carbs.
Glycogen is what muscles use as fuel. So supplementing your post-workout meal with caffeine could help you recover faster and function better for the rest of the day.
Other studies have shown that caffeine can enhance endurance performance, as well. In these studies, athletes who took caffeine before endurance exercise either covered more ground or covered the same ground in less time than those who did not take caffeine.
Caffeine’s potential benefits don’t end there. Caffeine Informer has outlined an even more extensive list that shows a host of other potential health benefits of caffeine.
But despite all these potential benefits, doctors caution against taking too much caffeine. After all, caffeine is still a drug, and more than a few people have paid the price for abusing it.
The Side Effects of Caffeine
Being in a prolonged state of stimulation takes its toll on both mind and body.
This is exactly what happens when you consume too much caffeine.
Eventually, the body starts to become more tolerant to the effects of caffeine. We all need rest. According to a study in the 1980s, your body’s response to caffeine binding to your adenosine receptors is to produce more adenosine receptors to negate the effect.
The result of this is two-fold – You become much more sensitive to adenosine, and in turn, need more caffeine to counter its effects. When there is suddenly no caffeine in the system, and all the adenosine is able to bind with their receptors, you crash.
When the body is accustomed to a regularly excessive serving size of caffeine, you crash hard. And the sudden absence of it can cause withdrawal symptoms.
Adenosine naturally widens blood vessels and increases blood flow. A surplus of adenosine will also cause more blood to flow through the wider blood vessels and accumulate in the brain. The result? A nasty headache that chronic coffee users are all too familiar with.
And in the absence of the serotonin production induced by caffeine, mood swings tend to occur. People become more easily agitated, irritated, anxious, and distracted.
One possible fix is to consume caffeine. But now that you understand how it works, you know that’s just a temporary solution. Failure to address the root of the problem will only save your agony for another day. And that problem is your caffeine intake.
Ultimately, prevention is the best cure. The most efficient way to reap all the benefits without having to deal with caffeine is to consume it regularly but in moderate amounts.
For most coffee brands, a moderate amount of coffee will give you a reasonably safe amount of caffeine. But a select few brands cater to coffee drinkers who just don’t get a kick out of normal coffee anymore–or, quite frankly, just find moderation boring.
Coffee Brands with Outrageously High Caffeine Content
Don’t expect a cup of coffee made from these brands to hit you like your brewed coffee from Dunkin’ Donuts, which has 180mg per 12 oz.
As you read this list, keep in mind that the maximum caffeine intake that is considered safe by the is 400 mg per day. Anything more than that level of caffeine in coffee is regarded as dangerous territory. But that’s exactly what all of these brands were going for..
Death Wish Coffee
Death Wish Coffee is a pioneer in the field of “world’s strongest coffee”. But even with more than thrice the amount of caffeine in a normal cup of coffee at 728 mg per 12 oz, Death Wish Coffee is the mildest of this bunch.
That doesn’t mean it doesn’t pack a mean punch, though. And it tastes excellent despite its caffeine content. It uses dark-roasted robusta coffee with a nutty, chocolatey flavor profile with hints of browned butter.
Death Wish Coffee is available as a whole bean and pre-ground options. It makes a strong black cup of joe with bold flavor that has set the bar high for its competitors.
If 728 mg of caffeine in a cup is a death wish, then Black Label‘s 1,554 mg of caffeine per cup of coffee is a death sentence. I’m not even sure if that’s a joke.
Devil Mountain Coffee Company’s Black Label coffee is the strongest in the world It’s also the most dangerous. If normal coffee works even a little bit for you, do not drink a Black Label coffee cup.
Though some like to tempt fate. In that case, Black Label prides itself in its dark roast blend that has a smooth, rich flavor with no bitterness. But a single cup has caffeine equivalent to 5 espresso shots! You’ll enjoy every sip, but be careful not to over do it!
Very Strong Coffee
Very Strong Coffee is right up there with Black Label in terms of the likelihood you’ll end up in the hospital. It has a caffeine content of 1,350 mg per cup of coffee.
One thing you can do to make your coffee experience safer is to use less of it in your brew. Even half a serving of Very Strong Coffee exceeds the suggested maximum safe allowance for caffeine. So, there’s no shame in dialing it down a bit; you’re still a badass for even trying a sip.
This bag is made up of 100% dark-roasted robusta beans, giving it a rich and indulgent taste. But unlike what you would expect, it’s not bitter at all. One of the main concerns about high-caffeine coffee is that it probably tastes bitter. But that’s not the case with Very Strong Coffee.
Last but not least is Black Insomnia. Good luck trying to get any sleep after drinking this, as it has 1,105 mg of caffeine per coffee cup. The amount may not measure up to some of the other brands before it (which isn’t necessarily bad in this context). But where it does have an advantage is taste.
Unlike most extreme brands, Black Insomnia is made with 80% robusta and 20% arabica beans. This gives it nice caramel, hazelnut, and macadamia aromas and a dark chocolate flavor. It’s a great balance between taste and performance, compromising neither of these. All in all, Black Insomnia provides an enjoyable (and sleepless) coffee experience.
Depending on how much of it you take, caffeine can be your greatest ally or your worst enemy. The key to being able to use it to your advantage is being informed about what it does, and how much of it is in the stuff you drink.
Caffeine sensitivity varies from person to person. So it’s also important to listen to your body and see how it responds to caffeine before being experimental with your coffee, or caffeine, journey. Just start with small amounts and work your way up as needed. Caffeinate responsibly!
Barista and coffee writer
Miguel Papa is a coffee fanatic with a passion for brewing. During the weekdays, you can find him experimenting with different drinks while he works as a barista. Otherwise, he’s likely writing here for Sip Coffee or enjoying the outdoors.