Dr Pepper vs Mr. Pibb (Pibb Xtra): caffeine compared
Mr. Pibb (Pibb Xtra) (12 oz) has 54 mg of caffeine, 13 mg more than Dr Pepper (12 oz, 41 mg) — 1.3× as much per serving. Per fluid ounce, Mr. Pibb (Pibb Xtra) is the stronger drink: 4.5 mg/oz versus 3.4 mg/oz.
| Dr Pepper | Mr. Pibb (Pibb Xtra) | |
|---|---|---|
| Serving | 12 oz | 12 oz |
| Caffeine per serving | 41 mg | 54 mg |
| Per fl oz | 3.4 mg | 4.5 mg |
| Share of 400 mg/day | 10% | 14% |
| Servings to reach 400 mg | 9.8 | 7.4 |
| Hours until under 50 mg | already under | 0.6 h |
| Last one for an 11 PM bedtime · standard (50 mg) | 11:00 PM | 10:27 PM |
| Last one for an 11 PM bedtime · sensitive (25 mg) | 7:26 PM | 5:27 PM |
| Share of the 200 mg pregnancy limit | 20% | 27% |
One serving of each, over 16 hours
Common questions
Which has more caffeine, Dr Pepper or Mr. Pibb (Pibb Xtra)?
Mr. Pibb (Pibb Xtra) (12 oz) has about 54 mg versus 41 mg in Dr Pepper (12 oz): 13 mg more, or 1.3× as much.
Which is stronger per ounce, Dr Pepper or Mr. Pibb (Pibb Xtra)?
Mr. Pibb (Pibb Xtra): about 4.5 mg per fl oz versus 3.4 mg for Dr Pepper. Serving size decides the total you actually drink.
How many Dr Pepper servings equal one Mr. Pibb (Pibb Xtra)?
About 1.3 servings of Dr Pepper (12 oz) match the caffeine in one Mr. Pibb (Pibb Xtra) (12 oz).
When should I stop drinking Dr Pepper or Mr. Pibb (Pibb Xtra) before bed?
For an 11 PM bedtime with a 50 mg limit and a 5-hour half-life: last Dr Pepper by 11:00 PM, last Mr. Pibb (Pibb Xtra) by 10:27 PM. Half-life varies from about 1.5 to 9.5 hours between people.
Method
Caffeine per labeled serving, from the same drink table every calculator here uses (FDA/USDA reference amounts and manufacturer labels; see caffeine content of every drink). Brewed drinks vary batch to batch, so read these as typical values. Decay uses a 5-hour average half-life with a 45-minute absorption ramp; cutoff = bedtime − 5 h × log₂(dose ÷ limit). Percentages use the FDA's 400 mg/day figure for healthy adults and the 200 mg/day limit ACOG gives for pregnancy.
Source — Dr Pepper: CSPI caffeine chart (Dr Pepper, 12 oz), checked 2026-10-13.
Source — Mr. Pibb (Pibb Xtra): Coca-Cola — Mr. Pibb (formerly Pibb Xtra), checked 2026-10-13. Caffeine content: 54 mg/12 fl oz.