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Coffee has more than three times the caffeine of green tea: about 95mg per 8oz cup of brewed coffee (USDA) against roughly 28mg for 8oz of green tea. Even a single 1oz espresso shot at 63mg more than doubles a cup of green tea. The one green-tea format that competes is matcha, which runs 20-45mg per gram of powder because you drink the whole ground leaf instead of an infusion.
The numbers
| Drink | Serving | Caffeine |
|---|---|---|
| Brewed coffee | 8oz | 95mg (USDA) |
| Espresso | 1oz shot | 63mg (USDA) |
| Black tea | 8oz | 47mg |
| Green tea | 8oz | ~28mg |
| Matcha | per gram of powder | 20-45mg |
The FDA considers up to 400mg per day generally safe for healthy adults.
Why green tea feels different, not just weaker
Green tea's reputation for a "calm alertness" is not only the smaller dose. Tea contains L-theanine, an amino acid that many drinkers report smooths caffeine's edge, and the slower sipping pace of hot tea spreads a small dose over a longer window. Coffee delivers three times the caffeine, usually faster, on a sharper curve. Neither is better; they are different tools. The mistake is expecting green tea to substitute one-for-one for coffee and then wondering why the morning feels flat.
Matcha, the exception
A cup of steeped green tea leaves most of the leaf's caffeine in the strainer. Matcha suspends the entire powdered leaf in water, so at 20-45mg per gram, a typical serving of a gram or two lands anywhere from black-tea territory to the edge of a small coffee. Cafe matcha lattes often use bigger scoops than home preparation, which is why they can carry more kick than the health-halo branding suggests; the drink gets its own breakdown in matcha latte caffeine.
Using green tea as the step-down
Swapping an afternoon 95mg coffee for a ~28mg green tea cuts that dose by roughly two thirds while keeping a warm-cup ritual intact, which is why it is the classic taper move for people fixing their sleep. Brew temperature matters more than with coffee: water just off the boil scorches green tea into bitterness, so a variable temperature kettle earns its counter space. Check the rest of your day's total against the caffeine database or the caffeine comparison tool.
Related reading
FAQ
How much less caffeine does green tea have than coffee? Green tea runs about 28mg per 8oz vs 95mg for brewed coffee, roughly a two-thirds reduction cup for cup.
Does matcha have as much caffeine as coffee? It can approach a small coffee. Matcha carries 20-45mg per gram of powder, so a two-gram serving may rival a weak cup, though 8oz of brewed coffee at 95mg usually still wins.
Is green tea enough to replace morning coffee? Dose-wise it is about a third of a coffee, so expect a gentler lift. Many people use it as an afternoon step-down rather than a morning replacement.
Sources: USDA FoodData Central (brewed coffee, espresso, tea); FDA guidance on caffeine. This page is information, not medical advice.
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