Caffeine comparison tool: any two drinks, side by side

Pick any two drinks. The tool shows caffeine per serving, per fluid ounce, and how many of each reach the FDA's 400mg daily context figure. Every number comes from a verified guide on this site, linked below the result.

For context, the FDA cites 400mg of caffeine a day as an amount generally not associated with negative effects in healthy adults. Tolerance varies; this is information, not advice. The full sourced tables live in the caffeine database.