General reference · Tea
How much caffeine is in Green tea?
This is a general estimate, not a figure for a particular brand. We haven’t rechecked the original USDA entry, its version or the serving conversion yet.
A representative brewed green tea value; individual products and brewing methods vary.
Interactive serving
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Where this figure comes from
- Source
- USDA FoodData Central
- Source type
- Government database
- Market
- General reference
- How we got the amount
- Authoritative reference
- Source reviewed
- 21 August 2026
Representative reference value; leaf, water temperature and brew time vary. This link opens the USDA database, not the exact food entry. Treat the serving amount as approximate. The date shown here does not mean we rechecked the original entry on that day.
Estimated caffeine remaining over time
These figures apply CaffCalc’s exponential model to the adjusted 29 mg starting value. They are calculations, not measurements of caffeine in a particular person.
| Hours elapsed | 3-hour half-life | 5-hour half-life | 7-hour half-life |
|---|---|---|---|
| 0 | 29 mg | 29 mg | 29 mg |
| 3 | 14.5 mg | 19.1 mg | 21.5 mg |
| 5 | 9.1 mg | 14.5 mg | 17.7 mg |
| 8 | 4.6 mg | 9.6 mg | 13.1 mg |
| 10 | 2.9 mg | 7.3 mg | 10.8 mg |
| 12 | 1.8 mg | 5.5 mg | 8.8 mg |
With the central five-hour model, the estimate falls below 25 mg after approximately 1.1 hours. The faster and slower columns show why one fixed clearance time shouldn’t be treated as a personal fact.
Use this caffeine value
Use this amount in a calculation, or save the drink to your tracker on this device.
Same category, lower documented dose
Looking for less caffeine?
Here are some drinks in the same category with less listed caffeine. This compares caffeine only, not overall health benefits. Check each drink’s source note before choosing.