Red Bull has more caffeine than Starbucks London Fog on both counts: 80mg per 8.4 oz can against 40mg per 16 oz grande (40mg at every size), and about 10mg per fluid ounce against 2. 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.
Red Bull vs Starbucks London Fog: the numbers
| Red Bull | Starbucks London Fog | |
|---|---|---|
| Caffeine per serving | 80mg per 8.4 oz can | 40mg per 16 oz grande (40mg at every size) |
| Caffeine per fl oz | 9.5mg | 2.5mg |
| Servings to reach 400mg (FDA context) | 5.0 | 10.0 |
Sources: Red Bull's figure is verified in our Red Bull caffeine guide against Red Bull label / Caffeine Informer (source); Starbucks London Fog's figure is verified in our Starbucks London Fog guide against Starbucks nutrition listing (source).
The concentration gap is the striking part: Red Bull packs roughly 4 times the caffeine per ounce. Sipping speed matters at that density; a 8.4 oz can finished in minutes hits differently than the same milligrams spread over a slow cup.
Which one should you pick?
Pick Starbucks London Fog when you want the lighter dose or a slower ramp, and Red Bull 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
- Red Bull: the full caffeine guide
- Starbucks London Fog: the full caffeine guide
- The verified caffeine database
FAQ
Does Red Bull or Starbucks London Fog have more caffeine? Red Bull: 80mg per 8.4 oz can versus 40mg per 16 oz grande (40mg at every size) for Starbucks London Fog.
Which is stronger per ounce? Red Bull, at about 9.5mg per fluid ounce versus 2.5mg for Starbucks London Fog.
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