Starbucks canned Nitro (Black) has more caffeine than Wide Awake iced coffee (Kroger) on both counts: 155mg per 9.6 oz can against 30mg per 13.7 oz bottle, and about 16mg per fluid ounce against 2. The serving sizes differ, so the table below shows both ways of counting.
Wide Awake iced coffee (Kroger) vs Starbucks canned Nitro (Black): the numbers
| Wide Awake iced coffee (Kroger) | Starbucks canned Nitro (Black) | |
|---|---|---|
| Caffeine per serving | 30mg per 13.7 oz bottle | 155mg per 9.6 oz can |
| Caffeine per fl oz | 2.2mg | 16.1mg |
| Servings to reach 400mg (FDA context) | 13.3 | 2.6 |
Sources: Wide Awake iced coffee (Kroger)'s figure is verified in our Wide Awake iced coffee (Kroger) caffeine guide against Caffeine Informer (source); Starbucks canned Nitro (Black)'s figure is verified in our Starbucks canned Nitro (Black) guide against PepsiCo product facts (source).
The concentration gap is the striking part: Starbucks canned Nitro (Black) packs roughly 7 times the caffeine per ounce. Sipping speed matters at that density; a 9.6 oz can finished in minutes hits differently than the same milligrams spread over a slow cup.
Which one should you pick?
Pick Wide Awake iced coffee (Kroger) when you want the lighter dose or a slower ramp, and Starbucks canned Nitro (Black) 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
- Wide Awake iced coffee (Kroger): the full caffeine guide
- Starbucks canned Nitro (Black): the full caffeine guide
- The verified caffeine database
- Every drink compared: the comparisons index
- Compare any two of 120+ drinks
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Gear from this guide
FAQ
Does Wide Awake iced coffee (Kroger) or Starbucks canned Nitro (Black) have more caffeine? Starbucks canned Nitro (Black): 155mg per 9.6 oz can versus 30mg per 13.7 oz bottle for Wide Awake iced coffee (Kroger).
Which is stronger per ounce? Starbucks canned Nitro (Black), at about 16.1mg per fluid ounce versus 2.2mg for Wide Awake iced coffee (Kroger).
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