How much caffeine is in black tea?
Black tea (237 ml) usually contains 14–48 mg of caffeine, about 31 mg on average.
Based on 2 g of dry leaf, 237 ml of water, about 5 min of steeping.
Key numbers
| Caffeine per cup | 14–48 mg |
|---|---|
| Volume | 237 ml |
| mg / 100 ml (average) | 13.1 |
| Compared with filter coffee (per cup) | 32% |
| Cups to reach 400 mg a day (adult) | 12 |
| Cups to reach 200 mg at once | 6 |
How caffeine changes with steeping
Longer steeping usually brings more caffeine. Figures for 2 g of tea.
| Steeping time | Caffeine per cup |
|---|---|
| 2 min | 9–31 mg |
| 3 min | 12–41 mg |
| 4 min | 13–45 mg |
| 5 min | 14–48 mg |
What about the evening?
After 6 hours roughly 4–26 mg of caffeine is still in the body (half-life 3–7 h). Sensitivity varies, so treat this as a guide, not a rule.
Frequently asked questions
How much caffeine is in black tea?
Black tea (237 ml) usually contains 14–48 mg of caffeine, about 31 mg on average. Based on 2 g of dry leaf, 237 ml of water, about 5 min of steeping.
Does black tea have more caffeine than filter coffee?
No, on average less: about 32% of the caffeine in a cup of filter coffee.
How many cups of black tea can I drink a day?
For adults EFSA gives up to 400 mg of caffeine a day from all sources. From this drink alone that is roughly 12 cups, if nothing else adds caffeine. In pregnancy the limit is 200 mg a day.
How does black tea compare with other teas and coffee?
See the "Caffeine in drinks" table: every drink is listed by caffeine per cup.
Try it
Sources and method
- Ayakdaş & Ağagündüz, Foods 2025;14(13):2313 (68 tea samples)
- Mayo Clinic: Caffeine content for coffee, tea, soda and more
- Caffeine Informer: brewed tea (lab averages and brew-time tests)
- EUFIC: EFSA opinion on the safety of caffeine (2015)
Data checked 2026-10-24. Ranges are shown because studies report different numbers. General information, not medical advice.