5-hour Energy (regular) has more caffeine than Starbucks London Fog on both counts: 200mg per 1.93 oz shot against 40mg per 16 oz grande (40mg at every size), and about 104mg 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.
5-hour Energy (regular) vs Starbucks London Fog: the numbers
| 5-hour Energy (regular) | Starbucks London Fog | |
|---|---|---|
| Caffeine per serving | 200mg per 1.93 oz shot | 40mg per 16 oz grande (40mg at every size) |
| Caffeine per fl oz | 103.6mg | 2.5mg |
| Servings to reach 400mg (FDA context) | 2.0 | 10.0 |
Sources: 5-hour Energy (regular)'s figure is verified in our 5-hour Energy (regular) caffeine guide against 5-hour Energy facts page (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: 5-hour Energy (regular) packs roughly 41 times the caffeine per ounce. Sipping speed matters at that density; a 1.93 oz shot 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 5-hour Energy (regular) 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
- 5-hour Energy (regular): the full caffeine guide
- Starbucks London Fog: the full caffeine guide
- The verified caffeine database
FAQ
Does 5-hour Energy (regular) or Starbucks London Fog have more caffeine? 5-hour Energy (regular): 200mg per 1.93 oz shot versus 40mg per 16 oz grande (40mg at every size) for Starbucks London Fog.
Which is stronger per ounce? 5-hour Energy (regular), at about 103.6mg 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.