Mountain Dew Baja Blast has more caffeine than A&W Root Beer: 59mg vs 0mg in the same 12 oz can. That is a 59mg gap, and since the cans match, the per-serving number is the whole story.
A&W Root Beer vs Mountain Dew Baja Blast: the numbers
| A&W Root Beer | Mountain Dew Baja Blast | |
|---|---|---|
| Caffeine per serving | 0mg per 12 oz can | 59mg per 12 oz can |
| Caffeine per fl oz | 0.0mg | 4.9mg |
| Servings to reach 400mg (FDA context) | n/a (caffeine-free) | 6.8 |
Sources: A&W Root Beer's figure is verified in our A&W Root Beer caffeine guide against Caffeine Informer (source); Mountain Dew Baja Blast's figure is verified in our Mountain Dew Baja Blast guide against PepsiCo product facts (source).
The concentration gap is the striking part: Mountain Dew Baja Blast packs roughly 492 times the caffeine per ounce. Sipping speed matters at that density; a 12 oz can finished in minutes hits differently than the same milligrams spread over a slow cup.
Which one should you pick?
Pick A&W Root Beer when you want the lighter dose or a slower ramp, and Mountain Dew Baja Blast 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
- A&W Root Beer: the full caffeine guide
- Mountain Dew Baja Blast: the full caffeine guide
- The verified caffeine database
- Every drink compared: the comparisons index
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FAQ
Does A&W Root Beer or Mountain Dew Baja Blast have more caffeine? Mountain Dew Baja Blast: 59mg per 12 oz can versus 0mg per 12 oz can for A&W Root Beer.
Which is stronger per ounce? Mountain Dew Baja Blast, at about 4.9mg per fluid ounce versus 0.0mg for A&W Root Beer.
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.
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