Full Throttle has more caffeine than Barq's root beer on both counts: 160mg per 16 oz can against 22mg per 12 oz can, and about 10mg 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 Full Throttle: the numbers
| Barq's root beer | Full Throttle | |
|---|---|---|
| Caffeine per serving | 22mg per 12 oz can | 160mg per 16 oz can |
| Caffeine per fl oz | 1.8mg | 10.0mg |
| Servings to reach 400mg (FDA context) | 18.2 | 2.5 |
Sources: Barq's root beer's figure is verified in our Barq's root beer caffeine guide against Coca-Cola brand data (source); Full Throttle's figure is verified in our Full Throttle guide against Caffeine Informer (source).
The concentration gap is the striking part: Full Throttle packs roughly 5 times the caffeine per ounce. Sipping speed matters at that density; a 16 oz can finished in minutes hits differently than the same milligrams spread over a slow cup.
Which one should you pick?
Pick Barq's root beer when you want the lighter dose or a slower ramp, and Full Throttle 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
- Full Throttle: the full caffeine guide
- The verified caffeine database
FAQ
Does Barq's root beer or Full Throttle have more caffeine? Full Throttle: 160mg per 16 oz can versus 22mg per 12 oz can for Barq's root beer.
Which is stronger per ounce? Full Throttle, at about 10.0mg per fluid ounce versus 1.8mg for Barq's 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.