Coffee, along with caffeine, is part of our daily lives for most of us. While many simply enjoy the taste of coffee, its popularity can also be attributed to the stimulant that helps you stay alert or get you through those hours after lunch.
But how much caffeine contains your daily cup to jump-start the morning? And how many cups is too many?
Keep reading if you want to learn about the factors that influence the caffeine content of coffee and how much caffeine your cup of coffee usually contains.
What Affects Caffeine Content?
The amount of caffeine in coffee varies considerably depending on several factors, such as the coffee beans, the brewing method, and the serving size.
Type of Coffee Beans
There are two popular coffee bean types, Arabica and Robusta. For those searching for a quick caffeine fix, Robusta is the better option as it contains higher amounts of caffeine. In fact, you will find double the amount of caffeine in a cup of Robusta coffee.
Roasting
Against popular belief, the roasting process has little effect on caffeine, as it is very stable during the roasting process.
What changes during the process, however, is the density of the bean. The longer the beans are roasted, the less dense they become because the water content is lost during the process. [1]
So, how does this matter when it comes to caffeine? Bean for bean, a light roast versus a dark roast contains approximately the same amount of caffeine. But depending on how you measure your coffee, the roast has an influence on the amount of caffeine.
If you measure it by scoops (i.e., by volume), lightly roasted coffee will have more caffeine since the beans are denser. However, dark roasts have more caffeine if you weigh out your beans because there is less mass.
Brewing Method
The extraction method plays a vital role in how much caffeine ends up in your cup of coffee. As water passes through the grounds, not only flavors are extracted along the way but also caffeine.
For the most part, the amount of caffeine extracted depends on 3 factors: the amount of time the grounds are in contact with water, the grounds’ coarseness, and the water’s temperature.
The longer you brew the coffee, the more caffeine will be extracted. Therefore, immersion methods tend to extract more caffeine.
But, as immersion methods usually use coarser grounds, this lessens the amount extracted. In addition, hot water extracts more caffeine than cold water. Cold brew coffee, for example, is left to sit for hours. But, as the grounds are coarse and it is immersed in cold water, the amount of caffeine won’t necessarily be higher than a French Press or a Pour-over coffee.
Serving Size & Amount of Ground Coffee
Of course, the serving size and the amount of ground coffee you use play an important role when it comes to caffeine content. A cup of coffee can range from 1-24oz (30-700ml). Needless to say, this makes a big difference in the caffeine content.
How Much Caffeine Is in a Cup of Coffee?
So, how much caffeine is in a cup of coffee?
| Coffee (standard size serving) | Caffeine content [mg] |
| Brewed coffee | 95 |
| Espresso shot | 63 |
| Espresso-based drinks | 63 |
| Instant coffee | 62 |
| Decaf coffee | 0.3 – 2 |
On average, one standard size (8oz) cup of brewed coffee contains 95mg of caffeine. [2]
Espresso contains more caffeine per volume compared to brewed coffee. One shot of 1oz (30ml) contains around 63mg.[3] Although the amount of caffeine per volume is much higher, it’s still lower in caffeine than a cup of brewed coffee.
Similarly, espresso-based drinks, including Americanos, cappuccinos, lattes, and macchiatos, all contain the same amount of caffeine since all you do is mix espresso shots with milk.
Instant coffee usually comes with less caffeine, around 62mg for one serving of 8oz.[4]
Although you would think decaf coffee is entirely free of caffeine, this is rarely the case. Amounts of caffeine range from 0.3mg for a 1oz espresso shot to 2mg for an 8oz brewed cup of coffee.[5] That being said, the caffeine content may vary according to the method of decaffeination used.
Caffeine Content In Commercial Brands
Caffeine levels in commercial fast food and coffee shop coffees vary wildly and often contain more caffeine than home-brewed coffee. One thing to look out for is the large cup sizes, notorious for commercial coffee brands.
Starbucks
Probably the best-known coffee chain worldwide, Starbucks offers a wide variety of coffee and cup sizes. Following are their cup sizes and corresponding caffeine contents.[6,7]
- Short (8 oz): 130 – 180 mg
- Tall (12 oz): 195 – 270 mg
- Grande (16 oz): 260 – 360 mg
- Venti (20 oz): 340 – 475 mg
- Shot of espresso: 75 mg
- Espresso-based drinks: 75 mg
- Decaf: 15 – 30 mg, depending on cup size
McDonald’s
McDonald’s sells coffee under their brand McCafe. They don’t provide information on the caffeine content of their beverages. Following are estimations of caffeine contents: [8]
- Small (12 oz): 109 mg
- Medium (16 oz): 145 mg
- Large (21–24 oz): 180 mg
- Espresso: 71 mg, (Double espresso: 142 mg)
- Espresso-based drinks: 71 mg
- decaf: 8-14 mg, depending on cup size
Dunkin’ Donuts
Another popular commercial brand that sells coffee is Dunkin’ Donuts. Their caffeine contents are as follows: [9,10]
- Small (10 oz): 215 mg
- Medium (16 oz): 302 mg
- Large (20 oz): 431 mg
- Extra large (24 oz): 517 mg
- Espresso: 75 mg
- Decaf: 53-128 mg
Is Caffeine Safe?
First, let’s point out that moderate consumption of coffee has a range of health benefits, such as a reduced risk of type 2 diabetes, liver diseases, and Alzheimer’s. [11,12,13,14]
But how much coffee is too much, and at what point does caffeine consumption become problematic?
The food and drug administration (FDA) considers 400 mg a day, or around 4-5 cups, as an amount that is safe to consume. [15]
It’s important to note that people react differently to caffeine. While some are very sensitive, others hardly react to it. The rate at which caffeine is metabolized plays an important role.
As certain soft drinks and tea contain caffeine as well, it’s easy to hit the recommended daily limit for the average adult.
If you get too much caffeine, you might experience a wide range of symptoms: They include anxiety, sleep disruptions, restlessness, upset stomach, headache, and feeling of unhappiness (dysphoria). [16,17,18]
Also, keep in mind that it takes a while for caffeine to leave your system, and a cup of coffee late at night might make it difficult to fall asleep.
How to Cut Down on Caffeine?
If you’re sensitive to caffeine and/or experienced any of the symptoms as mentioned above after one cup too many, here are some ways to cut down on your caffeine consumption:
- Brew just enough. Don’t make more coffee than you actually intend to drink.
- Order smaller sizes. Opt for the smallest size available.
- Try Decaf.
- Drink high-quality coffee and enjoy the experience. Choose quality over quantity.
- Remember that many beverages, such as tea and certain soft drinks, also contain caffeine. You might want to cut down on those too.
Bottom Line
To summarize, the average amount of caffeine in a standard-size cup of coffee is 95mg. However, this may vary depending on factors such as coffee beans used, brewing, roasting, and the serving size. As with everything, moderation is key to avoiding negative health effects of caffeine.
If you limit your daily consumption to 4-5 cups, you should be on the safe side. Drinking high-quality coffee consciously can be a good way to cut down on caffeine.
