Starbucks cold brew (grande) has more caffeine than Monster Ultra (Zero Ultra): 205mg vs 150mg in the same 16 oz grande. That is a 55mg gap, and since the servings match, the per-serving number is the whole story.
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.
Monster Ultra (Zero Ultra) vs Starbucks cold brew (grande): the numbers
| Monster Ultra (Zero Ultra) | Starbucks cold brew (grande) | |
|---|---|---|
| Caffeine per serving | 150mg per 16 oz can | 205mg per 16 oz grande |
| Caffeine per fl oz | 9.4mg | 12.8mg |
| Servings to reach 400mg (FDA context) | 2.7 | 2.0 |
Sources: Monster Ultra (Zero Ultra)'s figure is verified in our Monster Ultra (Zero Ultra) caffeine guide against Caffeine Informer (source); Starbucks cold brew (grande)'s figure is verified in our Starbucks cold brew (grande) guide against Starbucks menu data (source).
Which one should you pick?
Pick Monster Ultra (Zero Ultra) when you want the lighter dose or a slower ramp, and Starbucks cold brew (grande) 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
- Monster Ultra (Zero Ultra): the full caffeine guide
- Starbucks cold brew (grande): 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 Monster Ultra (Zero Ultra) or Starbucks cold brew (grande) have more caffeine? Starbucks cold brew (grande): 205mg per 16 oz grande versus 150mg per 16 oz can for Monster Ultra (Zero Ultra).
Which is stronger per ounce? Starbucks cold brew (grande), at about 12.8mg per fluid ounce versus 9.4mg for Monster Ultra (Zero Ultra).
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