Dunkin Refresher (medium) vs Starbucks London Fog: which has more caffeine?

Dunkin Refresher (medium) has more caffeine than Starbucks London Fog on both counts: 99mg per 24 oz medium against 40mg per 16 oz grande (40mg at every size), and about 4mg 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.

Dunkin Refresher (medium) vs Starbucks London Fog: the numbers

Sources: Dunkin Refresher (medium)'s figure is verified in our Dunkin Refresher (medium) caffeine guide against Tasting Table / Dunkin figures (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 Starbucks London Fog when you want the lighter dose or a slower ramp, and Dunkin Refresher (medium) 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

• Dunkin Refresher (medium): the full caffeine guide
• Starbucks London Fog: the full caffeine guide
• The verified caffeine database

FAQ

Does Dunkin Refresher (medium) or Starbucks London Fog have more caffeine? Dunkin Refresher (medium): 99mg per 24 oz medium versus 40mg per 16 oz grande (40mg at every size) for Starbucks London Fog.

Which is stronger per ounce? Dunkin Refresher (medium), at about 4.1mg per fluid ounce versus 2.5mg for Starbucks London Fog.