| Size | Caffeine | Of a day’s 400 mg | Calories |
|---|---|---|---|
| 8 fl oz | 48 mg | 12% | 2 |
| 12 fl oz | 72 mg | 18% | 4 |
| 16 fl oz | 96 mg | 24% | 5 |
How long does the caffeine in black tea last?
Caffeine has a half-life of about 5 hours in most adults, so half of the 48 mg is still working 5 hours later. At under 50 mg, a single serving is already below the level that tends to affect sleep.
| If you have it at | Left at 11 pm |
|---|---|
| 8 am | 6 mg |
| Noon | 10 mg |
| 3 pm | 16 mg |
| 6 pm | 24 mg |
Add everything you drank today in the caffeine calculator to see your own curve.
How does black tea compare?
| Drink | Serving | Caffeine |
|---|---|---|
| A Monster | 16 fl oz can | 164 mg |
| A Rockstar | 16 fl oz can | 164 mg |
| A Monster Zero Ultra | 16 fl oz can | 144 mg |
| An iced latte | 12 fl oz | 133 mg |
| A flavored latte | 12 fl oz | 130 mg |
| A latte | 12 fl oz | 130 mg |
| A cappuccino | 12 fl oz | 130 mg |
| An oat milk latte | 12 fl oz | 130 mg |
| An Americano | 12 fl oz | 127 mg |
| A mocha | 12 fl oz | 123 mg |
| Cuban coffee | 1 cafecito (2 fl oz) | 119 mg |
| Coffee | 8 fl oz | 96 mg |
| A sugar-free Red Bull | 8.4 fl oz can | 76 mg |
| A Red Bull | 8.4 fl oz can | 75 mg |
| Iced tea | 12 fl oz | 72 mg |
| An energy drink | 8 fl oz can | 72 mg |
| A shot of espresso | 1 shot (1 fl oz) | 64 mg |
| Black tea | 8 fl oz | 48 mg |
| A Diet Coke | 12 fl oz can | 43 mg |
| Oolong tea | 8 fl oz | 38 mg |
| A Coke | 12 fl oz can | 33 mg |
| Green tea | 8 fl oz | 29 mg |
| Hot chocolate | 8 fl oz | 7 mg |
| Dark chocolate | 1 square (8 g) | 4 mg |
Where do these numbers come from?
From the USDA’s record “Tea, hot, leaf, black”, in the USDA Food and Nutrient Database for Dietary Studies (FNDDS). Caffeine varies with the beans or leaves, how it’s brewed and the shop, so a coffee-shop drink can have noticeably more or less than this. Check the brand’s own figures when you can.
Sources
About the author
Jacob is a product designer and the founder of Tone. Before Tone, he co-founded Boba, an AI-native trading app, as its chief product officer, and designed products at Decrypt.
For healthy adults, for information only, and not medical advice. If you are pregnant, breastfeeding, under 18, or have a medical condition or a history of disordered eating, talk to a doctor or registered dietitian before changing how you eat.
