Dunkin Sparkd Energy (medium) carries more total caffeine per serving (144mg per 24 oz medium vs 120mg per 6.5 oz can), but ounce for ounce Starbucks Doubleshot Espresso & Cream is actually the stronger drink at about 18mg per fluid ounce against 6. Which one "has more caffeine" depends on whether you measure the container or the concentration.
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 Sparkd Energy (medium) vs Starbucks Doubleshot Espresso & Cream: the numbers
| Dunkin Sparkd Energy (medium) | Starbucks Doubleshot Espresso & Cream | |
|---|---|---|
| Caffeine per serving | 144mg per 24 oz medium | 120mg per 6.5 oz can |
| Caffeine per fl oz | 6.0mg | 18.5mg |
| Servings to reach 400mg (FDA context) | 2.8 | 3.3 |
Sources: Dunkin Sparkd Energy (medium)'s figure is verified in our Dunkin Sparkd Energy (medium) caffeine guide against Caffeine Informer Dunkin guide (source); Starbucks Doubleshot Espresso & Cream's figure is verified in our Starbucks Doubleshot Espresso & Cream guide against Caffeine Informer / Starbucks nutrition (source).
The concentration gap is the striking part: Starbucks Doubleshot Espresso & Cream packs roughly 3 times the caffeine per ounce. Sipping speed matters at that density; a 6.5 oz can finished in minutes hits differently than the same milligrams spread over a slow cup.
Which one should you pick?
Pick Starbucks Doubleshot Espresso & Cream when you want the lighter dose or a slower ramp, and Dunkin Sparkd Energy (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 Sparkd Energy (medium): the full caffeine guide
- Starbucks Doubleshot Espresso & Cream: the full caffeine guide
- The verified caffeine database
- Every drink compared: the comparisons index
FAQ
Does Dunkin Sparkd Energy (medium) or Starbucks Doubleshot Espresso & Cream have more caffeine? Dunkin Sparkd Energy (medium): 144mg per 24 oz medium versus 120mg per 6.5 oz can for Starbucks Doubleshot Espresso & Cream.
Which is stronger per ounce? Starbucks Doubleshot Espresso & Cream, at about 18.5mg per fluid ounce versus 6.0mg for Dunkin Sparkd Energy (medium).
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.