Home/Guides/Caffeine in Coffee, Tea & Energy Drinks
How much caffeine is really in your coffee, tea or energy drink? The honest answer: it varies enormously. A cup of decaf barely registers. A big cold brew or a coffee-chain order can carry more caffeine than a double espresso. Here’s the full range, drink by drink, and what it means for your day.
How much caffeine is in each drink?
Caffeine content isn’t really about coffee versus tea versus energy drinks as categories. It’s about dose per serving, and doses vary far more than most labels suggest. Below is a serving-by-serving reference, using USDA measurements for coffee and tea and each manufacturer’s own published nutrition facts for named products.
| Drink | Serving | Caffeine |
|---|---|---|
| Decaf tea | 8 oz (250 ml) | ~3 mg |
| Decaf coffee | 8 oz (240 ml) | ~5 mg |
| Green tea | 8 oz (250 ml) | ~30 mg |
| Coca-Cola Classic | 12 oz (355 ml) | 34 mg |
| Diet Coke | 12 oz (355 ml) | 46 mg |
| Black tea | 8 oz (250 ml) | ~50 mg |
| Latte | 10 oz (300 ml) | ~63 mg |
| Matcha tea | 8 oz (240 ml) | ~72 mg |
| Americano | 8 oz (240 ml) | ~77 mg |
| Red Bull | 8.4 oz (250 ml) | 80 mg |
| Brewed / drip coffee | 8 oz (240 ml) | ~95 mg |
| Espresso, double shot | 2 oz (60 ml) | ~125 mg |
| Cold brew | 10 oz (300 ml) | ~135 mg |
| Monster Energy (Original) | 16 oz (473 ml) | 160 mg |
| Starbucks Brewed Coffee, Grande | 16 oz (473 ml) | 310 mg |
Two things drive most of that range. Concentration: an espresso packs its caffeine into an ounce or two, so a double shot lands around 125 mg even though the cup is tiny. And volume: a coffee-chain grande or a 16 oz energy drink delivers more total caffeine simply because there’s more liquid in the cup. Order a large cold brew instead of a standard 10 oz serving and that same math can push a single drink past 200 mg.
A cup of decaf coffee and a grande brewed coffee from a coffee chain differ by roughly 60-fold in caffeine, and the FDA’s 400 mg daily line still sits above nearly every single serving on this list.
How much caffeine is safe in a day?
The US FDA cites 400 mg a day as an amount not generally associated with negative effects for healthy adults, roughly a Starbucks grande brewed coffee on its own, or four to five of the everyday cups on the list above. That’s a ceiling about sleep, jitters and heart rate, not hydration. Pregnant people and anyone sensitive to caffeine should aim lower.
The daily ceiling
~400 mg a day for healthy adults
That’s roughly four cups of brewed coffee, or a single large coffee-chain order on its own.
The FDA also notes some energy drinks alone can carry up to 250 mg in an 8 oz serving, so stacking a few caffeinated drinks in a day adds up faster than it feels.
Does the caffeine cancel out the hydration?
Caffeine is a real diuretic, just not at the doses in this list. A review of the evidence puts the threshold near 250 to 300 mg in one sitting before urine output rises meaningfully (Maughan & Griffin, 2003). Below that, and with regular use, the effect is minimal to absent; we cover the mechanism and the daily-drinker research in more depth in our coffee piece.
Look at the table again. A single serving of nearly everything on it sits under that threshold. Even a Starbucks grande brewed coffee at 310 mg is close, but that’s one large drink alone, not stacked on top of anything else. So a normal cup of coffee, tea or energy drink still counts as fluid. It just shouldn’t be your only fluid.
How to count caffeinated drinks toward hydration
Our honest answer: count each drink for the water it actually contains, and don’t let the caffeine number scare you off logging it. That’s what the Caffeine in Drinks tool does: look up any drink from the table above, adjust it to your own serving size, and see it against the 400 mg guidance in context.
It’s also why we built Brim to credit coffee, tea and energy drinks toward your daily goal (Premium), each a little below water on purpose. In our experience, real-world tracking should stay conservative rather than assume every caffeinated drink hydrates exactly like water; the credit percentages are visible to every user, free or not, right in the app.
Key takeaways
Caffeine spans roughly a hundredfold across common drinks, from about 3 mg in decaf tea to over 300 mg in a large coffee-chain brew.
A standard 8 oz cup of brewed coffee has about 95 mg; a double espresso concentrates about 125 mg into a couple of ounces.
The FDA’s 400 mg-a-day guidance for healthy adults sits above nearly every single serving here. It’s a sleep-and-jitters ceiling, not a hydration one.
At normal doses, caffeine is only a mild diuretic (Maughan & Griffin, 2003), so coffee, tea and energy drinks still count toward your fluid (Premium in Brim).
Frequently asked
How much caffeine is in a cup of coffee?
A standard 8 oz (240 ml) cup of brewed coffee has about 95 mg of caffeine, per USDA FoodData Central. A double espresso shot concentrates roughly 125 mg into about 2 oz.
How much caffeine is in tea?
Black tea runs about 50 mg per 8 oz cup, green tea about 30 mg, and matcha closer to 70 mg. Decaf tea carries only a trace, around 3 mg.
How much caffeine is in an energy drink?
An 8.4 oz can of Red Bull has 80 mg, about the same as a cup of coffee. A 16 oz can of Monster Energy carries roughly 160 mg, about double.
How much caffeine is safe in a day?
The US FDA cites 400 mg a day as an amount not generally associated with negative effects for healthy adults, roughly four cups of brewed coffee. That is a limit about sleep and jitters, not hydration.
Does Brim count caffeinated drinks toward my water goal?
Yes. Coffee, tea and energy drinks all count toward your daily goal (Premium), credited close to water since normal doses barely affect fluid balance. Free logging covers water only; the credit percentages are visible to everyone in the Caffeine in Drinks tool.
Keep reading
Sources
- 1.USDA FoodData Central (2026)
- 2.Manufacturer nutrition labels: Red Bull, Monster Energy, Coca-Cola and Starbucks (official product/nutrition pages) (2026)
- 3.US FDA, "Spilling the Beans: How Much Caffeine is Too Much?" (2018)
- 4.Maughan & Griffin, "Caffeine ingestion and fluid balance: a review," J. Hum. Nutr. Diet. (2003)
