Diet Mountain Dew has more caffeine than brewed green tea on both counts: 54mg per 12 oz can against 28mg per 8 oz cup, and about 4mg per fluid ounce against 4. The serving sizes differ, so the table below shows both ways of counting.
These are different categories of drink, which changes how the caffeine arrives. Energy drinks and sodas list an exact number because caffeine is a measured additive; brewed drinks vary with the beans and the brew, so their figures are compiled averages. The numbers here are the standard published values for each.
Diet Mountain Dew vs brewed green tea: the numbers
| Diet Mountain Dew | brewed green tea | |
|---|---|---|
| Caffeine per serving | 54mg per 12 oz can | 28mg per 8 oz cup |
| Caffeine per fl oz | 4.5mg | 3.5mg |
| Servings to reach 400mg (FDA context) | 7.4 | 14.3 |
Sources: Diet Mountain Dew's figure is verified in our Diet Mountain Dew caffeine guide against Caffeine Informer (source); brewed green tea's figure is verified in our brewed green tea guide against USDA FoodData Central (source).
Which one should you pick?
Pick brewed green tea when you want the lighter dose or a slower ramp, and Diet Mountain Dew 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
- Diet Mountain Dew: the full caffeine guide
- brewed green tea: the full caffeine guide
- The verified caffeine database
- Every drink compared: the comparisons index
- Compare any two of 120+ drinks
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Gear from this guide
FAQ
Does Diet Mountain Dew or brewed green tea have more caffeine? Diet Mountain Dew: 54mg per 12 oz can versus 28mg per 8 oz cup for brewed green tea.
Which is stronger per ounce? Diet Mountain Dew, at about 4.5mg per fluid ounce versus 3.5mg for brewed green 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.
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