Pure caffeine crystals in the palm of a hand.
September 13, 2022

Taiwan Oolong Tea vs. Coffee: Which Has Less Caffeine?

Many people start their day with a cup of coffee or tea. Most folks do this for the instant energy that caffeine brings. Caffeine is great for a quick pick-me-up, but finding the right daily allowance is essential to maintaining its benefits. Looking for something that strikes the right balance for you? In this article, we discuss how caffeine content in Taiwan Oolong tea compares with coffee to offer some helpful insights.

What is Caffeine?

Pure caffeine crystals in the palm of a hand.

Pure caffeine crystals

Caffeine is a naturally occurring substance found in coffee, tea, and cocoa beans. It’s also added to some sodas, energy drinks, and over-the-counter medications. When consumed, caffeine acts as a stimulant to the central nervous system, providing a temporary boost of energy. Caffeine can also have other effects on the body, including:

  • Increasing alertness
  • Increasing blood pressure
  • Increasing heart rate

Caffeine is absorbed into the bloodstream within 45 minutes of being consumed and its effects can last up to six hours.

Effects of Too Much Caffeine

 Cup of coffee

An adult in the US on average consumes about 135 mg of caffeine daily, or the amount in 1.5 cups of coffee (1 cup = 8 ounces). The U.S. Food and Drug Administration considers 400 milligrams (about 4 cups brewed coffee) a safe amount of caffeine for healthy adults to consume daily.

While moderate caffeine consumption may be good as a stimulant, too much can have adverse side effects. Too much caffeine can cause the following:

  • Restlessness and shakiness
  • Insomnia
  • Anxiety
  • Fast heart rate
  • Headaches
  • Dizziness
  • Dehydration
  • Tolerance, so you need to take more of it to get the same results

Caffeine in Coffee

There are many different types of coffee, from light roast to dark roast and everything in between. Each type of coffee has its own unique flavor profile and caffeine content, but there are no clearly defined parameters determining the caffeine content in coffee.

Glass cup in a pile of roasted coffee beans

On average, though, a cup (8oz.) of coffee has 95-200 mg of caffeine. However, the amount of caffeine in coffee can vary depending on the type of bean, the roast, and how it's brewed. For example, espresso has more caffeine than regular coffee because it's more concentrated.

Light roast coffee generally has more caffeine than dark roast coffee, though by a small amount. This is because the roasting process releases some of the caffeine, making it less potent. If you're looking for a coffee with less caffeine, opt for a heavy roast or decaf option. If you want a stronger cup of coffee, go for a lighter roast.

Coffee is usually brewed from grinds. Hot water passing over the fine grinds quickly extracts most of the caffeine, so it’s difficult to control the caffeine levels in the brewed coffee.

Caffeine in Taiwan Oolong Tea

The amount of caffeine in tea varies according to the type of tea. In general, black teas, which are more oxidized, have more caffeine than green teas, which are less processed. Taiwan Oolong Teas are somewhere in between black and green teas in terms of caffeine. Oolong teas typically have moderate amounts of caffeine.

Pouring Taiwan Oolong Tea

Taiwan’s Tea Research and Extension Station (TRES) measured the caffeine content of a number of Taiwan teas after brewing at different temperatures. The following table extrapolates the TRES data and summarizes the results for an 8oz. cup of tea prepared with boiling water using 4.7g of tea. 

Caffeine in an 8oz. (237ml) Cup of Tea
(Boiling Water, with 4.7g of tea)

 Tea Type Caffeine (mg)
High Mountain Oolong 63
Wenshan Baozhong 68
Dong Ding Oolong 69
Black Tea 99
Oriental Beauty 102


From this data, a typical brew of Taiwan Oolong, and tea in general, has far less caffeine than your average cup of coffee.

Other Factors Affecting Caffeine in Tea

Besides the type of tea, whether you use loose leaf tea or tea bags also plays a role in how much caffeine you get in your cup. Loose leaf tea gives you more control over the brewing of your tea and thereby more control over how much caffeine comes out.

Tea cup with tea and tea bag next to a teapot beside a cup of tea and loose leaf tea in a bamboo tea scoop.

Steep time and temperature of the water are big factors in how much caffeine is extracted. Caffeine easily dissolves in hot water. The hotter the water, the more caffeine dissolves. With loose leaf tea, you can easily control the temperature of the water and the amount of time the tea is left to steep.

Caffeine crystals on tea roasting oven

Caffeine crystals covering a tea roasting oven

Like roasting coffee, roasting tea also gets rid of some caffeine. Places that have roasted tea for a long time have caffeine crystals hanging off the walls and equipment. This is because the heat from roasting sublimes the caffeine, which then forms on the surrounding surfaces.

Caffeine Calculator

Want to know more about the caffeine in your tea and coffee? Check out our Caffeine CalculatorThis calculator helps you understand the caffeine content of your favorite drinks, including some popular store bought teas and coffees, and how much caffeine you’ve had in total throughout the day. Then, you’ll be able to decide if you should slow down, or go ahead and have one more cup!


Although Oolong tea and coffee both contain caffeine, coffee generally has more. This is because the brewing process for coffee concentrates the caffeine, making it more potent. With Oolong teas, and loose-leaf teas in general, you also have finer control over how you brew it. This gives you more control in how much caffeine ends up in your cup. So, if you're looking for a caffeine fix, but not too much, drinking tea is the way to go!

Let Us Know!

What did you think of this article? Have any questions? We really want to know what you think! Leave any thoughts or questions in the comment section below!


If you enjoyed this post and would like to hear more about the specialty tea industry here in Taiwan, follow us on YouTubeFacebook, and Instagram and please subscribe to our newsletter. Subscribe now and get US$5 off your first order!