What's more acidic, coffee or green tea? A pH comparison

December 3, 2025 •

2 min read

According to a 2022 scientific review, coffee can stimulate digestive processes, yet for those with acid sensitivity, a key question arises: what's more acidic, coffee or green tea? The answer often depends on preparation, but brewed coffee almost always has a lower pH.

Quick Summary

Coffee is generally more acidic than green tea, with average pH levels between 4.85 and 5.4, making it harder on sensitive stomachs. Green tea is typically closer to neutral (6.5 to 7.5 pH) and gentler on the digestive system.

Key Points

Coffee is more acidic: Brewed coffee typically has a pH of 4.85 to 5.4, making it moderately acidic.
Green tea is closer to neutral: The pH of green tea usually ranges from 6.5 to 7.5, making it much less acidic.
Brewing methods matter: A cold brew coffee is significantly less acidic than a hot brew, while a longer steeping time can increase green tea's acidity.
Acidity affects digestion: Coffee's acidity and caffeine can trigger acid reflux in sensitive individuals, whereas green tea is often gentler on the stomach.
Dark roasts reduce acidity: For coffee lovers, choosing a dark roasted coffee can help lower the acidity level compared to a light roast.
Additives change pH: Adding milk or cream to coffee or tea will reduce acidity, while lemon juice will increase it significantly.

Understanding the pH Scale

The pH scale, ranging from 0 to 14, measures acidity or alkalinity based on hydrogen ion concentration. A pH below 7 is acidic, 7 is neutral, and above 7 is alkaline. The scale is logarithmic, meaning a pH of 4 is ten times more acidic than a pH of 5.

The Acidity of Coffee

Brewed coffee typically has a pH between 4.85 and 5.4, classifying it as moderately acidic due to natural acids. Factors influencing coffee acidity include bean type (Arabica often higher than Robusta), roast level (darker roasts are less acidic), and brewing method (cold brew is significantly less acidic than hot brew). Brewing time can also play a role.

The Acidity of Green Tea

Green tea is generally less acidic than coffee, with a pH usually between 6.5 and 7.5, making it closer to neutral or slightly alkaline. Acidity varies by green tea type (Matcha is often near pH 7, while Sencha can be around pH 5.5), steeping time (longer steeping can increase acidity by releasing tannins), water quality, and additives.

Comparing Acidity: Coffee vs. Green Tea

Below is a comparison table:


Feature	Coffee	Green Tea
Average pH Range	4.85 – 5.4	6.5 – 7.5
Relative Acidity	Moderately acidic	Close to neutral or mildly acidic
Main Contributing Acids	Chlorogenic acids, quinic, citric, malic	Tannic acid, citric acid
Factors Increasing Acidity	Light roast, fine grind, hot brew	Longer steep time, adding lemon
Factors Decreasing Acidity	Dark roast, coarse grind, cold brew	Shorter steep time, adding milk

Factors Influencing Acidity in Your Brew

Several factors can alter the acidity of both coffee and green tea. Brewing temperature impacts the extraction of acidic compounds. Water quality, such as the mineral content of hard water, can influence the final pH. Additives like milk or cream increase pH, reducing acidity, while acidic additions like lemon juice decrease pH. Even storage can affect acidity due to oxidation.

Acidity and Digestive Health

For those with acid reflux or GERD, coffee's acidity and caffeine can be problematic, potentially relaxing the lower esophageal sphincter and increasing stomach acid. While moderate coffee is fine for many, green tea is often a gentler alternative due to its higher pH. Green tea's L-theanine also contributes to a calmer effect. However, excessive or strong green tea can still cause discomfort. Decaffeinated or shorter-steeped green tea can minimize irritation. You can find more information on coffee's digestive effects in this review: Coffee May Stimulate Digestion: New Review Findings.

Conclusion: Which Brew is Right for You?

Comparing coffee and green tea, coffee is more acidic (pH 4.85-5.4) than green tea (pH 6.5-7.5), making green tea generally preferable for acid sensitivity. The final acidity is influenced by preparation, bean/leaf type, and additions. For sensitive coffee drinkers, dark roasts, Robusta beans, or cold brew can reduce acidity. For green tea drinkers, managing steep time and avoiding acidic additives helps. The best choice depends on individual tolerance and preferences, but understanding pH is key for informed decisions.

Frequently Asked Questions

Green tea is typically close to neutral or mildly alkaline, with a pH range of 6.5 to 7.5, making it significantly less acidic than coffee.

For individuals with acid reflux, green tea is generally the better option because it is much less acidic and less likely to irritate the stomach. However, everyone's tolerance varies.

To make coffee less acidic, opt for dark roasts, Robusta beans, or a cold brewing method. Using a coarse grind and adding milk or cream can also help reduce acidity.

While green tea is much less acidic than coffee or sodas, frequent or prolonged exposure to its mild acidity could potentially harm tooth enamel over time. Drinking in moderation and rinsing your mouth afterward can mitigate this risk.

Yes, steeping green tea for longer periods, for example, over 5 minutes, can release more tannins and other acidic compounds, which lowers the tea's pH and increases its acidity.

Yes, cold brew coffee is generally less acidic than hot brewed coffee. The cold water extraction process inhibits the release of some of the acidic compounds found in the beans.

Yes, adding milk or cream to coffee introduces alkaline components that can buffer the coffee's natural acids. This raises the overall pH, making the beverage less acidic.