These studies show that certain components in both beverages have beneficial effects. The gist: Various studies have been done to discover the role of both green tea and coffee in improving brain function, weight loss, and disease prevention. Typically, the remaining caffeine content is 5%~15% of the original beans or leaves. However, much like decaffeinated coffee, decaffeinated green tea also isn’t completely caffeine-free, although its caffeine content is significantly lower. Most people probably know about decaf coffee but decaf green tea is a little harder to find. This is why cold-brewed coffee has a lower caffeine content than hot-brewed coffee.

Temperature - More caffeine is extracted into coffee brewed using higher temperatures.

Brewing Time - Another factor that affects how much caffeine is in coffee is the brewing time - the longer the brewing time is, the more caffeine is extracted.

Amount of coffee used - More coffee that goes into the brew also means a higher caffeine content.

This is based on the typical serving sizes for espresso (1 oz/shot) and brewed coffee (8 oz/cup).

Brewing Method - Between the brewing methods, such as drip coffee, percolator, and French press, and the espresso method, brewed coffee has been found to have more caffeine perserving.

The grind size of the coffee also has an effect on caffeine content, with finer grinds releasing more caffeine.

Coffee Species and Grind Size - Arabica has a lower caffeine content than Robusta.

Factors That Affect the Caffeine Content in Coffee *Based on analyses by Eurofins Scientific Inc. Iced tea, however, is generally brewed hot and then iced to cool down, so it has as much caffeine as a normal hot brew.

Brewing Method - Also related to temperature, cold-brewing extracts less caffeine into green tea than hot brewing.

This is why cold-brewed tea, while steeped longer, will still have less caffeine than hot-brewed tea.

However, brewing time is related to temperature since hotter water will also extract caffeine faster into the brew.

Brewing Time - Longer steeping/brewing will yield more caffeine.

Temperature - The higher the temperature, the more caffeine is extracted into the brew.

Harvest Time of Leaves - The harvest season of tea leaves can also affect caffeine content, with earlier harvests of the same plants having a higher caffeine content.

Tea Variety - The caffeine content in tea varies depending on the variety.

Factors That Affect the Caffeine Content in Green Tea Some coffees have more caffeine than others in the same way that some teas also have a higher caffeine content than others. Naturally, there are deviations to this since there are factors that can affect the caffeine content in both tea and coffee. In contrast, an 8 oz cup of green tea typically has 30 to 50 mg of caffeine. Based on the FDA’s estimate, an 8 oz cup of coffee typically contains 80 to 100 mg of caffeine.

The effects of caffeine can be felt faster in coffee since it has a higher caffeine content, but green tea has the added benefit of having L-theanine, which has a calming effect.Ĭoffee generally has more caffeine than green tea. brewing method and time vs tea variety/coffee species) affect the caffeine levels in the final brew.

Different factors, both within and outside the control of the drinker (e.g. The gist: Coffee generally has more caffeine than green tea, but certain factors can affect this, and in some cases, it can be the other way around. Green Tea vs Coffee | An In-Depth Comparison Here, we compare green tea and coffee from different angles to help you understand more about each beverage. The green tea vs coffee debate isn’t a new topic, but it’s often compared only for caffeine content or health benefits.

Caffeine in coffee