English breakfast tea has more caffeine than brewed oolong tea: 47mg vs 37mg in the same 8 oz cup. That is a 10mg gap, and since the cans match, the per-serving number is the whole story.
brewed oolong tea vs English breakfast tea: the numbers
| brewed oolong tea | English breakfast tea | |
|---|---|---|
| Caffeine per serving | 37mg per 8 oz cup | 47mg per 8 oz cup |
| Caffeine per fl oz | 4.6mg | 5.9mg |
| Servings to reach 400mg (FDA context) | 10.8 | 8.5 |
Sources: brewed oolong tea's figure is verified in our brewed oolong tea caffeine guide against USDA FoodData Central (source); English breakfast tea's figure is verified in our English breakfast tea guide against Twinings published figure (source).
Which one should you pick?
Pick brewed oolong tea when you want the lighter dose or a slower ramp, and English breakfast tea when you actually need the bigger hit and know your tolerance. If you are stacking either with other caffeinated drinks through the day, run the math against the 400mg reference rather than guessing.
For context, the FDA cites 400mg of caffeine a day as an amount generally not associated with negative effects in healthy adults. Tolerance and health vary, so treat these numbers as information, not advice.
Related reading
- brewed oolong tea: the full caffeine guide
- English breakfast tea: the full caffeine guide
- The verified caffeine database
- Every drink compared: the comparisons index
FAQ
Does brewed oolong tea or English breakfast tea have more caffeine? English breakfast tea: 47mg per 8 oz cup versus 37mg per 8 oz cup for brewed oolong tea.
Which is stronger per ounce? English breakfast tea, at about 5.9mg per fluid ounce versus 4.6mg for brewed oolong tea.
Comparing caffeine? The caffeine comparison tool puts hundreds of drinks side by side, and the caffeine curfew calculator can check your cutoff time for tonight.