How much caffeine is in Mountain Dew Zero Sugar?
A 12 fl oz can of Mountain Dew Zero Sugar has 68 mg of caffeine.
That's about three quarters of a cup of brewed coffee, and 17% of the 400 mg a day the FDA cites for most healthy adults.
Source: Center for Science in the Public Interest · checked 10 Nov 2026
When did you have it?
Had at 3 pm, about 24 mg is still in you at an 11 pm bedtime. That should not affect most people’s sleep.
Your whole day, every drink, in the free CaffeineIQ check. The iPhone app is coming soon.
Latest time to drink it
For an 11 pm bedtime, most people should finish a 12 fl oz can of Mountain Dew Zero Sugar by about 8:20 pm. The table works it out for other bedtimes and for how sensitive you are: it is the latest time to start one so that the caffeine left stays under the line all night.
| Bedtime | Very sensitive under 25 mg | Average under 50 mg | Not very sensitive under 100 mg |
|---|---|---|---|
| 9 pm | 1:15 pm | 6:15 pm | Any time |
| 10 pm | 2:15 pm | 7:20 pm | Any time |
| 11 pm | 3:15 pm | 8:20 pm | Any time |
| Midnight | 4:15 pm | 9:15 pm | Any time |
| 1 am | 5:15 pm | 10:15 pm | Any time |
For a 12 fl oz can of Mountain Dew Zero Sugar, average clearance (half-life 5 h), 8 hours of sleep. "Any time" means even one at bedtime stays under the line.
How long it lasts
The caffeine from a 12 fl oz can of Mountain Dew Zero Sugar peaks in your blood about 75 minutes after you start it, at roughly 58 mg. Half of it is gone in about 5 hours for an average adult; that ranges from roughly 3 to 7 hours, and longer in pregnancy or with some medicines.
| Time after | 3 hours | 6 hours | 9 hours | 12 hours |
|---|---|---|---|---|
| Still in you | 48 mg | 32 mg | 21 mg | 14 mg |
So one had at 3 pm leaves about 24 mg at 11 pm. How long caffeine lasts explains the curve.
How it compares
Mountain Dew Zero Sugar is stronger than 93% of the 15 sodas we track, by caffeine per serving.
Per fluid ounce (5.7 mg) it is stronger than 93% of them.
To reach 400 mg in a day you would need about 6 of these.
Less caffeine
- Olipop Citrus Rush 60 mg, 12 fl oz can
- Poppi Alpine Blast 55 mg, 12 fl oz can
- Diet Mountain Dew 54 mg, 12 fl oz can
More caffeine
- fritz-kola 83 mg, 330 ml bottle
FAQ
Is Mountain Dew Zero Sugar high in caffeine?
It is moderate. A 12 fl oz can of Mountain Dew Zero Sugar has 68 mg, which is 72% of the 95 mg in an 8 fl oz cup of brewed coffee.
Can I drink Mountain Dew Zero Sugar at night?
Earlier is better. Had at 7 pm, it leaves about 42 mg in an average adult at an 11 pm bedtime. The latest time for an 11 pm bedtime is about 8:20 pm.
How long does the caffeine in Mountain Dew Zero Sugar last?
It peaks about 75 minutes after you start it. Of the 68 mg, about 32 mg is still in you 6 hours later and 14 mg after 12 hours, for an average adult with a 5-hour half-life.
Does Mountain Dew Zero Sugar have more caffeine than a cup of coffee?
No. A 12 fl oz can of Mountain Dew Zero Sugar has 68 mg; an 8 fl oz cup of coffee has 95 mg.
Method and limits
The caffeine figure comes from Center for Science in the Public Interest; recipes, brewing and batches vary, so a real serving can differ. The curves use a standard one-compartment model with an average 5-hour half-life and a sleep-friendly line of 50 mg; your own body may clear caffeine faster or slower. How it works has the details.
These are estimates for information, not medical advice.