How much caffeine is in coffee?
General information only. This article explains the basics and is not medical advice. For anything about your own health, talk to a doctor or other qualified professional.
Quick answer
An 8-ounce (240 ml) cup of brewed coffee contains about 95 mg of caffeine, though it can range from roughly 80 to 100 mg or more. A single shot of espresso has about 63 mg.
A shot of espresso tastes stronger than a mug of drip coffee, but the mug usually wins on caffeine. Espresso is more concentrated, while a full cup simply contains more coffee.
Caffeine in coffee and other drinks
Typical amounts, which vary by brand and how the drink is made:
| Drink | Serving | Caffeine (approx.) |
|---|---|---|
| Brewed coffee | 8 oz (240 ml) | 95 mg |
| Espresso | 1 shot (1 oz / 30 ml) | 63 mg |
| Instant coffee | 8 oz | 60–65 mg |
| Decaf coffee | 8 oz | 2–15 mg |
| Black tea | 8 oz | 47 mg |
| Green tea | 8 oz | 28 mg |
| Cola | 12 oz can | 30–40 mg |
| Energy drink | 8 oz | 70–100 mg |
Coffee shop sizes add up fast. A large 16 to 20 ounce brewed coffee can easily contain 300 mg or more. Here’s how ounces and cups compare if you’re converting serving sizes.
What changes the amount
- Bean type: Robusta beans contain roughly twice as much caffeine as Arabica.
- Brewing method: Longer contact with water, as in cold brew, often extracts more.
- Ratio: More grounds per cup means more caffeine.
How much caffeine is too much?
According to the FDA, up to 400 mg a day, about four cups of brewed coffee, is generally not linked to harmful effects in healthy adults. People react differently, though, and limits can be lower during pregnancy or with certain health conditions, so it’s worth asking a doctor about your own situation.
Sources
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