How much is too much?
The U.S. FDA says up to about 400 mg a day is generally not linked to negative effects for most healthy adults. People who are pregnant, sensitive to caffeine, taking certain medicines or under 18 should aim lower; ask a doctor about your own limit.
How long it stays with you
Caffeine's half-life is about 5 hours on average (it ranges widely, from about 2 to 10 hours). Here is roughly how much is left after one serving:
| Hours later | Caffeine left |
|---|---|
| 0 h | 200 mg |
| 2 h | 152 mg |
| 4 h | 115 mg |
| 6 h | 87 mg |
| 8 h | 66 mg |
| 10 h | 50 mg |
| 12 h | 38 mg |
That is why an afternoon coffee can still affect sleep. The caffeine calculator adds up a whole day.
Compared with other drinks
| Drink | Serving | Typical caffeine |
|---|---|---|
| cold brew (16 oz) | 16 oz glass | 200 mg |
| nitro cold brew | 12 oz | 200 mg |
| brewed coffee (16 oz) | 16 oz cup | 190 mg |
| iced coffee (16 oz) | 16 oz glass with ice | 165 mg |
| brewed coffee (12 oz) | 12 oz cup | 140 mg |
| a mocha | 12 oz, 1–2 shots + chocolate | 130 mg |
| a double espresso | 2 oz double shot | 126 mg |
| a latte | 12 oz, 1–2 shots | 126 mg |
| a cappuccino | 8–12 oz, 1–2 shots | 126 mg |
| an americano | 12 oz, 2 shots | 126 mg |
| a flat white | 6–8 oz, 2 shots | 126 mg |
| a cortado | 4 oz, 2 shots | 126 mg |
| moka pot coffee | 2 oz serving | 105 mg |
| French press coffee | 8 oz cup | 100 mg |
2027 Coffee Journal & Brew Log · $6.99
Log every bag, recipe and rating, and find your perfect ratio faster. Printable.
Take a lookQuestions people ask
How much caffeine is in cold brew (16 oz)?
About 200 mg in a 16 oz glass serving, usually 150–280 mg.
How many servings of cold brew (16 oz) can I have a day?
About 2 servings would reach 400 mg, the FDA's general guideline for healthy adults. Many people feel best well below that.
Numbers on this page are estimates calculated from the assumptions shown. Coffees, beans and drinks vary; caffeine figures are typical values, not medical advice.