Starbucks Flat White has more caffeine than Starbucks Caffe Mocha: 195mg vs 175mg in the same 16 oz grande. That is a 20mg gap, and since the servings match, the per-serving number is the whole story.
Starbucks Flat White vs Starbucks Caffe Mocha: the numbers
| Starbucks Flat White | Starbucks Caffe Mocha | |
|---|---|---|
| Caffeine per serving | 195mg per 16 oz grande | 175mg per 16 oz grande |
| Caffeine per fl oz | 12.2mg | 10.9mg |
| Servings to reach 400mg (FDA context) | 2.1 | 2.3 |
Sources: Starbucks Flat White's figure is verified in our Starbucks Flat White caffeine guide against Starbucks nutrition listing (source); Starbucks Caffe Mocha's figure is verified in our Starbucks Caffe Mocha guide against Starbucks nutrition listing (source).
Which one should you pick?
Pick Starbucks Caffe Mocha when you want the lighter dose or a slower ramp, and Starbucks Flat White 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
- Starbucks Flat White: the full caffeine guide
- Starbucks Caffe Mocha: 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 Starbucks Flat White or Starbucks Caffe Mocha have more caffeine? Starbucks Flat White: 195mg per 16 oz grande versus 175mg per 16 oz grande for Starbucks Caffe Mocha.
Which is stronger per ounce? Starbucks Flat White, at about 12.2mg per fluid ounce versus 10.9mg for Starbucks Caffe Mocha.
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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