Peace Tea carries more total caffeine per serving (23mg per 23 oz can vs 22mg per 12 oz can), but ounce for ounce Barq's root beer is actually the stronger drink at about 2mg per fluid ounce against 1. 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.
Barq's root beer vs Peace Tea: the numbers
| Barq's root beer | Peace Tea | |
|---|---|---|
| Caffeine per serving | 22mg per 12 oz can | 23mg per 23 oz can |
| Caffeine per fl oz | 1.8mg | 1.0mg |
| Servings to reach 400mg (FDA context) | 18.2 | 17.4 |
Sources: Barq's root beer's figure is verified in our Barq's root beer caffeine guide against Coca-Cola brand data (source); Peace Tea's figure is verified in our Peace Tea guide against Caffeine Informer (source).
Which one should you pick?
Pick Barq's root beer when you want the lighter dose or a slower ramp, and Peace Tea 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
- Peace Tea: the full caffeine guide
- The verified caffeine database
- Every drink compared: the comparisons index
FAQ
Does Barq's root beer or Peace Tea have more caffeine? Peace Tea: 23mg per 23 oz can versus 22mg per 12 oz can for Barq's root beer.
Which is stronger per ounce? Barq's root beer, at about 1.8mg per fluid ounce versus 1.0mg for Peace Tea.
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.