Barq's root beer vs Starbucks London Fog: which has more caffeine?

Starbucks London Fog has more caffeine than Barq's root beer on both counts: 40mg per 16 oz grande (40mg at every size) against 22mg per 12 oz can, and about 2mg 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.

Barq's root beer vs Starbucks London Fog: the numbers

Sources: Barq's root beer's figure is verified in our Barq's root beer caffeine guide against Coca-Cola brand data (source); Starbucks London Fog's figure is verified in our Starbucks London Fog guide against Starbucks nutrition listing (source).

Which one should you pick?

Pick Barq's root beer when you want the lighter dose or a slower ramp, and Starbucks London Fog 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

• Barq's root beer: the full caffeine guide
• Starbucks London Fog: the full caffeine guide
• The verified caffeine database
• Every drink compared: the comparisons index

FAQ

Does Barq's root beer or Starbucks London Fog have more caffeine? Starbucks London Fog: 40mg per 16 oz grande (40mg at every size) versus 22mg per 12 oz can for Barq's root beer.

Which is stronger per ounce? Starbucks London Fog, at about 2.5mg per fluid ounce versus 1.8mg for Barq's root beer.