Key Takeaways

• Decaf coffee is not 100% caffeine-free. Due to the nature of any decaf process, a trace amount of caffeine remains.
  
• The caffeine content in a brewed cup of decaf typically ranges from 3–15 mg, varying significantly based on factors such as brewing method and serving size.
  
• On average, we find that a cup of decaf has about 10% of the caffeine of a regular coffee
  

How much caffeine is typically in a cup of decaf coffee?

One of the questions we're asked most frequently at Swiss Water is "How much caffeine is in a cup of decaf?" Most people know that even decaffeinated coffee is not 100% caffeine-free. Due to the nature of decaf processing—any method of decaf processing—it's just not possible to get every single molecule of caffeine out of a coffee bean (unless you remove the flavors that make coffee taste like coffee).

But what does this mean in real-world terms if you're trying to avoid caffeine for health reasons, or limit caffeine for any reason, and want to know how much you're taking in?

The answer is a hard one to give. In truth, there are so many variables (like the method of brewing or amount of coffee used) involved in bringing a decaf coffee from us to you that the precise amount of caffeine in your final cup is literally always going to vary.

We are also aware of a range of results from different peer-reviewed studies. A 2006 study from the University of Florida College of Medicine in Gainesville found caffeine content in a cup of brewed decaf landed somewhere between 3–15 mg, depending on the size of the coffee and the method (shot of espresso or 16 oz brewed).

On average, we find that a cup of decaf has about 10% of the caffeine of a regular coffee, which works out to a little less caffeine than you’d find in an ounce of dark chocolate, or less than half the amount of caffeine in a can of Coke.

Why is it hard to measure caffeine in decaf coffee?

There are a few reasons. While we guarantee that any decaffeinated green (unroasted) coffee that comes out of the Swiss Water® Process is 99.9% caffeine free—how much of that 0.1% ends up being consumed can vary.

The Swiss Water® Process is only one stage in a coffee's journey. After it leaves our hands, coffee goes to the roaster, where how a coffee is roasted can affect remaining caffeine levels.

Unfortunately, the effects of roasting are consistently inconsistent, according to both our research and that of others. Which is to say that we can't know for sure how much caffeine levels will be reduced by any particular style of roasting, be it light or super-dark, though the process rarely has a huge impact on caffeine content.

How does brewing affect caffeine levels in decaf?

Once a decaf coffee is roasted, there's also the matter of brewing it. Here are a few notable things that can affect caffeine levels by as much as a few milligrams per cup.

• Brewing Method: The technique used to prepare your coffee, whether it's an espresso shot, a French press, or a pour-over, affects the final caffeine concentration in your cup.
  
• Brewing Strength and Time: A stronger brew generally yields more caffeine. This is often achieved by using finer grounds, a higher coffee-to-water ratio (more grounds), or allowing a longer contact time (brew time) between the coffee and water.
  
• Coffee Quantity: Simply put, the more coffee grounds you use in your preparation, the more total caffeine will be available to be extracted into your final beverage.

What should caffeine-sensitive individuals consider?

If caffeine sensitivity is an issue for you, we recommend trying a variety of beans and brewing methods to see which decaf feels best for your body and your lifestyle.

We know it's frustrating to not have a specific answer that fits all people and all situations, but at the end of the day, caffeine comfort and safety is going to be a personal decision for each individual, and for those with health concerns regarding caffeine, we always recommend consulting with a medical doctor.

If you opt to drink decaf, starting with a process that results in 99.9% caffeine-free coffee, and does so without adding any chemical solvents like the Swiss Water® Process, is the best way to set yourself up for success.

Cheers!