How much caffeine is in Pepsi? A 12 oz can of Pepsi has 38 mg and a 20 oz bottle has 63 mg, according to PepsiCo's caffeine table. Pepsi Zero Sugar has exactly the same amounts, 38 mg per can and 63 mg per 20 oz, and Diet Pepsi has slightly less: 35 mg per can and 59 mg per 20 oz.
That makes a can of Pepsi a little stronger than a can of Coke and well under an 8 oz cup of brewed coffee, which has about 95 mg. To see what an evening Pepsi leaves in you at bedtime, the caffeine calculator does the math for your own times.
Free toolCaffeine Cutoff CalculatorHow much caffeine is still in you at bedtime, and your latest cup.How much caffeine is in each size of Pepsi?
Pepsi and Pepsi Zero Sugar both run about 3.2 mg per fluid ounce, and Diet Pepsi about 2.9 mg. These figures come from PepsiCo's official US caffeine table, checked in November 2026.
| Size | Pepsi | Pepsi Zero Sugar | Diet Pepsi |
|---|---|---|---|
| 7.5 fl oz mini can | 24 mg | 24 mg | 22 mg |
| 12 fl oz can | 38 mg | 38 mg | 35 mg |
| 16 fl oz | 47 mg | ||
| 16.9 fl oz bottle | 53 mg | 53 mg | 50 mg |
| 20 fl oz bottle | 63 mg | 63 mg | 59 mg |
| Fountain, 12 fl oz | 38 mg | ||
| For comparison: brewed coffee, 8 oz | about 95 mg |
Pepsi Wild Cherry matches regular Pepsi (38 mg per 12 oz, 63 mg per 20 oz), and Pepsi-Cola Made with Real Sugar has 38 mg per 12 oz. Blank cells are sizes PepsiCo's table doesn't list for that drink. Formulas can change, so if the label on your can shows a different number, go with the label.
How much caffeine is in Pepsi Zero Sugar?
PepsiCo's current table lists 38 mg per 12 oz can of Pepsi Zero Sugar, the same as regular Pepsi. The 20 oz bottle has 63 mg.
You'll still see 69 mg per can quoted in a lot of places. That number is out of date: PepsiCo's own table now lists 38 mg. The difference matters at night. At 69 mg, a can would need about 7 hours 20 minutes to fall below 25 mg; at 38 mg it takes about 3 hours.
How much caffeine is in a can of Pepsi?
A standard 12 oz can of Pepsi has 38 mg of caffeine. A 7.5 oz mini can has 24 mg, about two thirds as much. A 12 oz fountain Pepsi also has 38 mg, so a large fountain cup scales up from there: a 24 oz cup would be about 76 mg before the ice takes up any room.
How much caffeine is in a 20 oz Pepsi?
A 20 oz bottle of Pepsi or Pepsi Zero Sugar has 63 mg of caffeine, and a 20 oz Diet Pepsi has 59 mg. That's about the same as a single shot of espresso (about 63 mg), and roughly two thirds of a cup of brewed coffee. The 16.9 oz bottle has 53 mg.
Does Pepsi have more caffeine than Coke?
Yes, slightly. A 12 oz Pepsi has 38 mg and a 12 oz Coke has 34 mg. Diet is the reverse: Diet Pepsi has 35 mg per can, while Diet Coke has 46 mg.
| Soda, 12 oz can | Caffeine |
|---|---|
| Diet Pepsi | 35 mg |
| Coca-Cola or Coke Zero Sugar | 34 mg |
| Pepsi or Pepsi Zero Sugar | 38 mg |
| Diet Coke | 46 mg |
| Mountain Dew | 54 mg |
So if you want the lowest-caffeine cola from these two brands, Diet Pepsi and regular Coke are close to a tie, and Diet Coke is the strongest. For every Coke product, see how much caffeine is in Coke; for Pepsi's citrus sibling, see how much caffeine is in Mountain Dew.
Pepsi vs coffee: which has more caffeine?
Coffee, by a wide margin. An 8 oz cup of brewed coffee has about 95 mg, which is about two and a half cans of Pepsi. Even the 20 oz bottle, at 63 mg, falls short of a cup of coffee.
Pepsi Zero Sugar vs coffee works out the same way, since it has the same 38 mg per can. Where soda catches up is volume: three cans through an afternoon come to 114 mg, more than a coffee. For a wider comparison, the caffeine in drinks chart puts sodas, tea and energy drinks side by side.
What's the latest time to drink a Pepsi before bed?
For an 11 PM bedtime, finish a 12 oz can of Pepsi by about 8 PM and a 20 oz bottle by about 4:20 PM. These are the times each drink falls below 25 mg by bedtime, using the site's average 5-hour half-life.
| Bedtime | Pepsi or Zero Sugar, 12 oz (38 mg) | Diet Pepsi, 12 oz (35 mg) | Pepsi, 16.9 oz (53 mg) | Pepsi, 20 oz (63 mg) | Diet Pepsi, 20 oz (59 mg) |
|---|---|---|---|---|---|
| 9:00 PM | 5:59 PM | 6:34 PM | 3:35 PM | 2:20 PM | 2:48 PM |
| 10:00 PM | 6:59 PM | 7:34 PM | 4:35 PM | 3:20 PM | 3:48 PM |
| 10:30 PM | 7:29 PM | 8:04 PM | 5:05 PM | 3:50 PM | 4:18 PM |
| 11:00 PM | 7:59 PM | 8:34 PM | 5:35 PM | 4:20 PM | 4:48 PM |
| Midnight | 8:59 PM | 9:34 PM | 6:35 PM | 5:20 PM | 5:48 PM |
In hours before bed, that's about 3 hours for a can of Pepsi, 2 hours 26 minutes for Diet Pepsi, 5 hours 25 minutes for a 16.9 oz bottle and 6 hours 40 minutes for a 20 oz. A 7.5 oz mini can starts at 24 mg, already under the line.
How much Pepsi caffeine is left at bedtime?
A 20 oz Pepsi at 7 PM still leaves about 36 mg in you at 11 PM, more than a whole fresh can. The table uses the calculator's math: remaining caffeine = dose x 0.5^(hours / 5), for an 11 PM bedtime.
| Drink at | Mini can (24 mg) | 12 oz can (38 mg) | 20 oz (63 mg) | Two cans (76 mg) | Diet 12 oz (35 mg) | Diet 20 oz (59 mg) |
|---|---|---|---|---|---|---|
| 3 PM | 8 mg | 13 mg | 21 mg | 25 mg | 12 mg | 19 mg |
| 5 PM | 10 mg | 17 mg | 27 mg | 33 mg | 15 mg | 26 mg |
| 7 PM | 14 mg | 22 mg | 36 mg | 44 mg | 20 mg | 34 mg |
| 9 PM | 18 mg | 29 mg | 48 mg | 58 mg | 27 mg | 45 mg |
This site uses about 25 mg at bedtime as a sensible ceiling. It isn't an official limit, just a useful line. One can with dinner is usually fine; a big bottle with dinner usually isn't.
These are averages. Some people clear caffeine much more slowly, and pregnancy and some medications can stretch it out a lot. Falling asleep fine doesn't mean caffeine had no effect: in an at-home study, a large dose taken 6 hours before bed cut total sleep by more than an hour. For the hour-by-hour curve, see how long caffeine lasts.
How many Pepsis a day is too much?
For healthy adults, the FDA cites 400 mg of caffeine a day as an amount not generally linked to negative effects. That's about ten 12 oz cans of Pepsi or six 20 oz bottles, before any coffee or tea.
The 400 mg figure is for adults. The FDA notes that too much caffeine in children and teens can cause a racing heart, anxiety and sleep problems, so a 20 oz bottle in the evening is a poor fit for them.