G Fuel Energy (can) has more caffeine than Red Bull on both counts: 300mg per 16 oz can against 80mg per 8.4 oz can, and about 19mg per fluid ounce against 10. The serving sizes differ, so the table below shows both ways of counting.
G Fuel Energy (can) vs Red Bull: the numbers
| G Fuel Energy (can) | Red Bull | |
|---|---|---|
| Caffeine per serving | 300mg per 16 oz can | 80mg per 8.4 oz can |
| Caffeine per fl oz | 18.8mg | 9.5mg |
| Servings to reach 400mg (FDA context) | 1.3 | 5.0 |
Sources: G Fuel Energy (can)'s figure is verified in our G Fuel Energy (can) caffeine guide against G Fuel product page (source); Red Bull's figure is verified in our Red Bull guide against Red Bull label / Caffeine Informer (source).
Which one should you pick?
Pick Red Bull when you want the lighter dose or a slower ramp, and G Fuel Energy (can) 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
- G Fuel Energy (can): the full caffeine guide
- Red Bull: 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 G Fuel Energy (can) or Red Bull have more caffeine? G Fuel Energy (can): 300mg per 16 oz can versus 80mg per 8.4 oz can for Red Bull.
Which is stronger per ounce? G Fuel Energy (can), at about 18.8mg per fluid ounce versus 9.5mg for Red Bull.
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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