NOS Energy has more caffeine than Starbucks London Fog: 160mg vs 40mg in the same 16 oz can. That is a 120mg gap, and since the cans 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.
Starbucks London Fog vs NOS Energy: the numbers
| Starbucks London Fog | NOS Energy | |
|---|---|---|
| Caffeine per serving | 40mg per 16 oz grande (40mg at every size) | 160mg per 16 oz can |
| Caffeine per fl oz | 2.5mg | 10.0mg |
| Servings to reach 400mg (FDA context) | 10.0 | 2.5 |
Sources: Starbucks London Fog's figure is verified in our Starbucks London Fog caffeine guide against Starbucks nutrition listing (source); NOS Energy's figure is verified in our NOS Energy guide against Caffeine Informer (source).
The concentration gap is the striking part: NOS Energy packs roughly 4 times the caffeine per ounce. Sipping speed matters at that density; a 16 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 NOS Energy 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 London Fog: the full caffeine guide
- NOS Energy: the full caffeine guide
- The verified caffeine database
FAQ
Does Starbucks London Fog or NOS Energy have more caffeine? NOS Energy: 160mg per 16 oz can versus 40mg per 16 oz grande (40mg at every size) for Starbucks London Fog.
Which is stronger per ounce? NOS Energy, at about 10.0mg per fluid ounce versus 2.5mg for Starbucks London Fog.
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.