What Coffee Has the Most Caffeine? The Real Numbers

Are you falling asleep in line at the coffee shop again after just drinking coffee a few hours ago? Should you take an espresso, a flat white, or a brewed coffee? What about the roast: light or dark?

If you’re like me and you like your cup of coffee with an extra kick in the butt, you may be wondering: what coffee has the most caffeine?

Sources: US Food and Drug Administration, Caffeine Informer, National Coffee Association

Type of Bean

Now that you know how much caffeine is in coffee, you’re probably wondering where the substance comes from. There are various sources of caffeine, but the most well-known are coffee beans. There are two main species of coffee plant that find their way to your cup: Arabica and Robusta.

In general, Arabica beans are regarded as higher quality than Robusta beans. Though Robusta plants are much easier to farm than Arabica, they have a strong, bitter-earth taste. Arabica, on the other hand, is known for its sweet and fruity flavors.

Arabica may be the more popular of the two, yet Robusta is the clear winner in the caffeine competition. On average, Robusta beans have twice as much caffeine content as Arabica beans (1).

Robusta is easy to find as it is almost always the bean of choice for cheaper, supermarket-ready brands. Though most craft roasters use Arabica beans, you can find high quality Robusta roasts with a little digging.

Type of Roast

There is a popular myth floating around that darker roasts have more caffeine than light profile roasts.  Unlike the myth of the Loch Ness monster (oh, it’s real), these roasts do not have more caffeine than light roasts. Many coffee know-it-alls say that lighter roasts have the most caffeine, but they are wrong as well.

Bean for bean, both roasts have about the same amount of caffeine (​2​​​), though it is a bit more complicated than that.

Related: Is caffeine bad?

When beans are roasted, they lose some of their mass, so dark-roasted beans, which have been cooked longer, weigh less than light-roasted beans. Therefore, a pound of dark roast will have slightly more beans than a pound of beans roasted lighter.

When you brew, if you measure out your beans by volume (like with a scoop), the light roast will produce a more caffeinated cup of coffee. However, if you measure by weight, then the darker roast brewed coffee will have more caffeine. If you’re scratching your head right now, don’t worry, this puzzle had me confused for a while as well.

Look at it this way: One cup of coffee that is roasted on a light profile is going to have more caffeine than one cup roasted darker, because the lighter the roast, the heavier and denser the beans. Though the volume is the same, the light roast will have more mass.

If you measure out 20 grams of each roast (dark and light), it will have more caffeine because it has more volume. Both weigh the same, but since darker roasted beans are less dense, you will have more of them.

Still confused? Check this explanatory video below, or read our guide on different coffee roasts.

Type of Beverage

Decaf coffee, espresso, drip — different coffee drinks contain different amounts of caffeine. It may seem that a standard 8 oz. cup of brewed coffee (drip coffee) has less caffeine compared to espresso, but it actually doesn’t.

The caffeine content of your average 8 oz. drip coffee is around 94.8 mg (3), whereas the caffeine content of a shot of espresso (about 1 ounce) is around 62.8 mg (4). There will be some nasty side effects of unknown caffeine intake, so keep reading.

So if we are comparing coffee drinks, then drip coffee is the better choice; however, espresso has more caffeine per volume than brewed coffee (drip coffee). For every ounce, espresso has about 60-80 mg of caffeine. The caffeine content of drip coffee is only 9–18 mg per ounce.

The caffeine content of a coffee drink also depends on its serving size. If you make your espresso a double shot then you are getting either just as much or more caffeine than you would with a regular cup of drip coffee, yet it’s going to take quite a bit of espresso to beat the dreaded 20 oz. Starbucks Venti.

Decaf coffee still has small traces of caffeine, and instant coffee is subject to differing levels of caffeine. More about different types of coffee here.

THE VERDICT – What Type of Coffee Has the Most Caffeine?

So which coffee has the most caffeine? Well, that depends, there are a few option. These highly caffeinated beans have been engineered to have high amounts of caffeine. Just be sure you’re aware of a safe amount of caffeine intake before consuming coffee like this, or you can also use this caffeine overdose calculator as your guide. Always remember: the health benefits of coffee can be great in moderation.

A double shot of espresso will beat a standard size drip brew any day of the week, but it can’t beat any drip brew over 10 oz. Regardless, if you want to ensure high caffeine content, then choose whichever is brewed with Robusta coffee beans.

Let me know if you have any questions in the comments below. And please share this article if you enjoyed it!