Caffeine Free Coca-Cola vs Diet Coke: which has more caffeine?

Diet Coke has more caffeine than Caffeine Free Coca-Cola: 46mg vs 0mg in the same 12 oz can. That is a 46mg gap, and since the cans match, the per-serving number is the whole story.

Caffeine Free Coca-Cola vs Diet Coke: the numbers

Sources: Caffeine Free Coca-Cola's figure is verified in our Caffeine Free Coca-Cola caffeine guide against Caffeine Informer (source); Diet Coke's figure is verified in our Diet Coke guide against Caffeine Informer (source).

The concentration gap could not be simpler: Caffeine Free Coke has no caffeine at all, so the Diet Coke figure of 46mg per 12 oz can is the entire difference.

Which one should you pick?

Pick Caffeine Free Coca-Cola when you want the lighter dose or a slower ramp, and Diet Coke 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

• Caffeine Free Coca-Cola: the full caffeine guide
• Diet Coke: the full caffeine guide
• The verified caffeine database
• Every drink compared: the comparisons index
• Compare any two of 120+ drinks

FAQ

Does Caffeine Free Coca-Cola or Diet Coke have more caffeine? Diet Coke: 46mg per 12 oz can versus 0mg per 12 oz can for Caffeine Free Coca-Cola.

Which is stronger per ounce? Diet Coke, at about 3.8mg per fluid ounce versus 0.0mg for Caffeine Free Coca-Cola.