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How much caffeine is in your coffee cup?

Learn the difference between good and bad caffeine before brewing your next cup.
Written by Lena Borrelli, Contributing Writer

It's official: America has a love affair with coffee. 

More than 95% of Americans consume caffeine, whether it is food, soda, or coffee. In fact, the average U.S. adult consumes up to 260 milligrams each day. With coffee vying for the spot of America's favorite drink, it brings up an important question: how much caffeine is in coffee, and how much is safe for your health?

Using today's latest studies and statistics, this is what we found. 

Also: Best espresso machine

That morning cup of coffee could be costing you more than you realize. The average 8-ounce cup of coffee contains between 80mg and 100mg of caffeine, but few Americans stop at just one cup. The more coffee you drink, as well as the type of coffee and brewing method, can all affect how much caffeine you consume each day. For example, your single-serve coffee machine may put out a smaller or weaker portion than your French press. However, while an espresso machine provides smaller amounts, it can be significantly stronger than your average cup of joe that you brew in your normal coffee maker.

What coffee has the most caffeine?

Certain brands may contain more caffeine than others. For example, Devil Mountain Black Label is considered the strongest coffee in the country. Other types of coffee with high caffeine content include these products.


Best for


Caffeine Content per 12oz cup



Devil Mountain Black Label

The strongest coffee in the U.S.



  • Arabica and Robusta Blend


  • Organic blend


  • Great body
  • Newer product


  • Can be inconsistent

Very Strong Coffee

Runner-up for the strongest coffee



  • 100% high-caffeine Robusta beans


  • Rich, intense flavor


  • Barrel-roasted
  • Very high caffeine content


  • Can taste bitter

High Voltage

A dark roast with high caffeine content



  • Shockingly strong


  • Sustainably grown and dark-roasted


  • Nespresso compatibility
  • Best for smaller batches


  • Made in Australia

Black Insomnia

A flavorful blend loaded with caffeine



  • Macadamia, caramel, and hazelnut flavors


  • Rare blend of beans

  • Triple the caffeine of Starbucks


  • Weaker strength

Biohazard Coffee

A pre-ground dark roast



  • Non-bitter Robusta beans


  • Non-GMO, 
  • Organic and Fair Trade


  • Conveniently pre-ground
  • Highest caffeine content


  • Missing full-bodied flavor of Arabica beans


  • Lacking depth of flavor

What is the strongest type of coffee?

The strongest brand of coffee comes from Devil Mountain with its Black Label dark roast. It has been tested at 1,035mg per 12oz.  

How you brew your coffee can also impact how much caffeine you consume. 

  • Brewed coffee: 95mg. 

  • Decaf brew: 2mg.

  • Cold brew: 153mg. - 238mg. per 12 oz. cup

  • Instant coffee: 62mg.

  • Espresso: 63mg. per 1 oz. shot

When determining how much caffeine you can drink each day, consider how you brew your coffee for accurate measurements. 

Can I test the caffeine content of my coffee?

Most grocery stores stock caffeine-testing strips, but you can order them from a reputable online seller if your local store does not carry them. Be sure to test your strips on black coffee to ensure that the test is not corrupted by milk or sugar.

Soak the strip for 30 seconds, and then check the lines marked "D" or "C." When the "C" line is darker, beverages contain less than 20mg. of caffeine, while a bolder "D" line indicates more than 20mg. of caffeine. If you receive unclear results, try again. 

Does caffeine really improve focus or performance?

Just one cup of coffee could show extra benefits, such as improved focus, better exercise, and greater fat burning. According to Healthline, coffee is actually recommended by the U.S. Special Forces as a way to sharpen focus. 

Studies have also shown that coffee can increase fat-burning while creating higher endorphin levels that promote health and wellness within the body.

What are the other benefits of coffee?

Caffeine is unique in that it enters the bloodstream near immediately, peaking anywhere from 30 to 120 minutes and lasting about three or four hours. It affects several systems, including your nervous system, while also affecting your hormones, endorphins, and muscles. 

Coffee can have a number of benefits:

  • Improve energy: Coffee has been shown to act as a stimulant, increasing energy levels, thanks to the inclusion of caffeine.

  • Burn fat: Caffeine is also known to help with fat burning. 

  • Gain essential nutrients: From just one cup of coffee, you can gain riboflavin, Vitamin B5), potassium, and magnesium.

  • Lower risk of Type 2 diabetes: Coffee can lower your chances of getting diabetes by as much as 67% in some cases.

  • Prevent dementia: Coffee can help protect you from Alzheimer's Disease, Parkinson's, and other neurodegenerative diseases.

  • Lower depression: Studies show that women who drink a minimum of four cups of coffee per day are 20% less at risk of depression than women who do not.

  • Fight cancer: Coffee has been shown to lower the risk of certain cancers, including liver and colorectal cancer, by up to 40%.

What are the potential negative side effects of coffee?

Caffeine is a stimulant. Too much can trigger or exacerbate anxiety, tremors, headaches, insomnia, irritability, and it can cause temporary increases in blood pressure. Ingesting caffeine regularly can also lead to dependency and withdrawal symptoms such as headaches and muscles aches. 

For more on the benefits and potential drawbacks of caffeine, see The Effects of Caffeine on Your Body from Healthline. 


How much caffeine is too much?

The important thing about caffeine is knowing how much is too much. Mayo Clinic suggests up to 400 milligrams of caffeine each day for healthy adults. 

This is the same as the following:

  • Two energy shot drinks

  •  Four cups of brewed coffee

  • 10 cans of soda

As the old adage goes, moderation is key.

Can you overdose on caffeine?

A study published in the U.S. National Library of Medicine shows that just 80 to 100 micrograms/milliliter can prove lethal. These levels can be attained by ingesting roughly 10 grams or greater.

Lethal overdoses from the overconsumption of caffeine do not happen often, but they are possible. This can be the result of a bad reaction to your medications or from too many energy drinks. However, studies show that caffeine overdoses from coffee and tea are rare.

Caffeine FAQ

How much caffeine does coffee have?

The average cup of coffee holds about 95 mg. of caffeine. However, the amount of coffee you drink and the brewing method can affect the amount of caffeine, changing your actual consumption.

Does espresso have more caffeine than coffee?

Espresso generally contains about 65 mg. of caffeine, which is less than the average cup of coffee. However, the serving size is much smaller, thanks to extra fine grounds from a coffee grinder

That means if you drink multiple shots of espresso, you can quickly surpass the amount of caffeine in your cup of coffee.

Can I overdose from drinking too much coffee?

Overdoses from excessive caffeine are extremely rare, but they can happen. The Food and Drug Administration (FDA) suggests a maximum of 400 mg. of caffeine per day per adult to help ensure good health.

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