May 23, 2019 4 min read

How Much Caffeine is in Coffee?

How Much Caffeine is in a Cup of Coffee

It may surprise you to learn that a shot of espresso has less caffeine than an 8-ounce cup of brewed coffee. Tossing back an espresso shot faster than a cup of coffee, may make you feel like you are getting a solid caffeine blast, however, in the long run your cup of coffee will help you win the marathon. 


47-64 MG per 1 oz


50 MG per 2 oz


100 MG per 8 oz


107.5 MG per 8 oz


95-165 MG per 8 oz


3-16 MG per 1 oz


6 MG per 8 oz 

What is Caffeine?

The majority of coffee drinkers associate caffeine as the main compound in coffee. However, there are over one thousand compounds in coffee and caffeine only makes up about .01% of coffee’s composition.  Pure caffeine powder is actually a white powdery substance that is very bitter. Why are we so interested in learning about the caffeine molecule and caffeine structure?  Caffeine does have a  significant impact on the body.  Learn more about caffeine in one of our articles: How Caffeine Works on the Body where we explore what creates differences in levels of caffeine in coffee and learn how much caffeine is in a cup of coffee.

What is the Caffeine Content in Coffee Trees?

What is interesting to note is that a species of coffee plant also has differences in caffeine content.  Researcher Dr. Arnot found one other lesser known factor in caffeine content; the altitude a coffee plant is grown at can also affect also its caffeine level.  Why? Caffeine is a plants natural insect repellant and at higher altitudes, fewer insects leads to less caffeine, and at lower altitudes with more insects, the caffeine is more concentrated. The other factors that play a role in the amount of caffeine in a cup of coffee are the roast, the grind, and the brewing method.

How Much Caffeine in Robusta Coffee Beans Versus Arabica Coffee Beans?

Green robusta coffee beans have almost twice the caffeine as green arabica coffee beans. There is a difference in caffeine content within the variations of each of these species of coffee trees as well. This may be a disappointment for caffeine loving coffee connoisseurs because you know you will not find Robusta coffee beans in your delicious gourmet coffee beans. Robusta coffee beans are very bitter. (Remember, pure caffeine is a bitter compound.)  Robusta coffee beans are usually used in less expensive instant coffee and some espressos like Italian espresso. Arabica coffee beans, are softer and more complex. When roasted properly this complexity is found in the roasted coffee. Arabica coffee beans allow experienced coffee roasters the ability to work with a wider palette of flavors. They can apply their craft, and the chemistry of coffee to create numerous gourmet coffees, single origin coffees and coffee blends.

How Processing and Preparing Coffee Affect Caffeine Content

Contrary to popular belief, caffeine levels remain virtually unchanged after green coffee bean are roasted into black coffee beans. Lighter roasts have a higher concentration of caffeine per bean than darker roasts because more caffeine is burned off in the longer roasting time, but pound per pound the caffeine content difference is insignificant. 

Aside from type of coffee used in the beverage, the actual concentrations of caffeine depend primarily on the grind, method of brewing, temperature and extraction time so absolute measurements are nearly impossible. Regarding the type of coffee grind, in general if other variables such as amount of coffee used, amount of hot water, brew length are consistent, the finer the grind, the more caffeine is extracted. The interesting exception to that rule is with cold brew. The higher the temperature of the water (not to exceed 205 degrees) the better extraction. Again, this is given that all the other variables remain the same. 

The final item to consider in how much caffeine is in a cup of coffee is the brewing. The chart below shows how much caffeine is in each coffee drink. On the far right, we've indicated the concentration of caffeine per ounce. Although, an eight ounce cup of coffee has more caffeine than an espresso shot, the espresso has a higher concentration of caffeine. So a double shot Americano, will essentially have the same amount of caffeine as a cup of brewed coffee.

Does Decaf Coffee Have Caffeine?

Yes, decaffeinated coffee does have some caffeine. Please take a look at the chart above, you will see there is caffeine in decaf coffee, although a small amount of caffeine is in brewed decaf coffee it can be a significant amount of caffeine in a decaf espresso shot.

How is Decaf Coffee Made?

How is decaf coffee made? The decaffeination process does not remove caffeine entirely from the coffee bean. The espresso style brewing method has a higher rate of extraction due to smaller grind size and temperature, so if you are looking for less caffeine, then your best coffee drink is either hot decaffeinated coffee or cold brew decaffeinated coffee.

How Much Caffeine is Too Much?

The average amount of caffeine consumed per day per person is about 300 milligrams. The majority of the caffeine content comes from coffee, soft drinks and tea, with less than 2.3 milligrams per day attributed to food.

Caffeine affects several hormone and neurotransmitter levels in the body. The main hormone responsible for your buzz is the same one that gets released when you are about to get eaten by a lion, adrenaline. Adrenaline increases blood pressure, heart rate, and respiratory rate, and too much adrenaline can give you the jitters.

We should review caffeine consumption. So how much caffeine is too much caffeine? Scientists have found that 400 mg /day is the safest average dose of caffeine for adults. This translates into around three, eight-ounce cups of coffee or eight cups of black tea. These quantities do vary because we all metabolize caffeine differently. Typically, it can take four to six hours for your body to metabolize half of what you consumed. So, a cup of coffee at dinner may keep you awake at bedtime.

Scientists have also found that caffeine becomes toxic around 10 grams. This is around 75 cups of coffee or 180 cups of black tea. We hope this is a far reach for most coffee and tea drinkers. We recommend that you follow a healthy lifestyle and keep an eye on the amount of caffeine you consume.  

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