How much caffeine is in half-caff coffee?
A small pot (20 fl oz, 4 cups) of half-caff coffee has 120 mg of caffeine.
That's about one and a half cups of brewed coffee, and 30% of the 400 mg a day the FDA cites for most healthy adults.
Source: USDA FoodData Central · checked 10 Nov 2026
When did you have it?
Had at 3 pm, about 42 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 small pot (20 fl oz, 4 cups) of half-caff coffee by about 4:10 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 | 9:10 am | 2:10 pm | 7:20 pm |
| 10 pm | 10:10 am | 3:10 pm | 8:20 pm |
| 11 pm | 11:10 am | 4:10 pm | 9:20 pm |
| Midnight | 12:10 pm | 5:10 pm | 10:20 pm |
| 1 am | 1:10 pm | 6:10 pm | 11:20 pm |
For a small pot (20 fl oz, 4 cups) of half-caff coffee, 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 small pot (20 fl oz, 4 cups) of half-caff coffee peaks in your blood about 75 minutes after you start it, at roughly 102 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 | 84 mg | 56 mg | 37 mg | 24 mg |
So one had at 3 pm leaves about 42 mg at 11 pm. How long caffeine lasts explains the curve.
How it compares
Half-caff coffee is stronger than 81% of the 22 coffees made at home we track, by caffeine per serving.
Per fluid ounce (5.9 mg) it is stronger than 11% of them.
To reach 400 mg in a day you would need about 3½ of these.
Less caffeine
- Nescafé Instant Coffee 113 mg, 12 fl oz cup
- Chicory Coffee 96 mg, 8 fl oz cup
- Coffee 95 mg, 8 fl oz cup
More caffeine
- Nespresso Diavolitto 150 mg, 1 espresso
- Death Wish Coffee 140 to 210 mg, 6 fl oz cup
- Nespresso Vertuo Coffee 170 to 200 mg, 7.77 fl oz cup
Same caffeine: Nespresso Kazaar.
FAQ
Is half-caff coffee high in caffeine?
Yes. A small pot (20 fl oz, 4 cups) of half-caff coffee has 120 mg, which is 1.3 times an 8 fl oz cup of brewed coffee (95 mg).
Can I drink half-caff coffee at night?
Not if you want to sleep well. Had at 7 pm, it leaves about 73 mg in an average adult at an 11 pm bedtime, above the 50 mg most people sleep fine with. The latest time for an 11 pm bedtime is about 4:10 pm.
How long does the caffeine in half-caff coffee last?
It peaks about 75 minutes after you start it. Of the 120 mg, about 56 mg is still in you 6 hours later and 24 mg after 12 hours, for an average adult with a 5-hour half-life.
Does half-caff coffee have more caffeine than Red Bull?
Yes. A small pot (20 fl oz, 4 cups) of half-caff coffee has 120 mg; an 8.4 fl oz can of Red Bull has 80 mg.
Method and limits
The caffeine figure comes from USDA FoodData Central; 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.