How much caffeine is in Red Bull? An 8.4 oz (250 ml) can has 80 mg, a 12 oz can has 114 mg, a 16 oz can has 151 mg and a 20 oz can has 198 mg, according to Red Bull. Red Bull Sugarfree has exactly the same amounts. A small can is roughly one cup of brewed coffee.
The bigger question for sleep is how much of that can is still in you at bedtime. With an average caffeine half-life of about 5 hours, a 16 oz can at 2 PM still leaves about 43 mg at 11 PM. The caffeine calculator runs the same math for your own can, bedtime and sensitivity.
Free toolCaffeine Cutoff CalculatorHow much caffeine is still in you at bedtime, and your latest cup.How much caffeine is in each size of Red Bull?
Red Bull lists 80 mg for 8.4 oz, 114 mg for 12 oz, 151 mg for 16 oz and 198 mg for 20 oz. These are the figures on the company's US and international Q&A pages, checked in October 2026.
| Can size | Caffeine (Red Bull's figure) | About the same as |
|---|---|---|
| 8.4 fl oz (250 ml) | 80 mg | one 8 oz cup of brewed coffee |
| 12 fl oz (355 ml) | 114 mg | a little more than one coffee |
| 16 fl oz (473 ml) | 151 mg | about one and a half coffees |
| 20 fl oz (591 ml) | 198 mg | about two coffees |
| 500 ml* | about 160 mg | about one and two thirds coffees |
*Red Bull's pages don't list a 500 ml figure. The estimate is scaled from 80 mg per 250 ml, so treat it as approximate and check the can.
The amount grows in step with the can: Red Bull works out to roughly 9.5 to 10 mg per fluid ounce at every size. So the can size, not the flavor, decides most of your dose.
How much caffeine is in a 12 oz Red Bull?
A 12 oz Red Bull has 114 mg of caffeine. That's about 34 mg more than the small can, and for an 11 PM bedtime it needs to be finished by about noon to drop below 25 mg by bed.
How much caffeine is in a 16 oz Red Bull?
A 16 oz (473 ml) Red Bull has 151 mg of caffeine. It's the size that catches most people out, because it's close to two small cans. At an average 5-hour half-life it takes almost 13 hours to fall below 25 mg.
Is Red Bull stronger than coffee?
A small 8.4 oz Red Bull (80 mg) has a bit less caffeine than an 8 oz cup of brewed coffee (about 95 mg). Red Bull itself describes the small can as about the same as a cup of home-brewed coffee.
The comparison flips with size. A 16 oz Red Bull at 151 mg is more than an average cup of coffee, and the 20 oz can at 198 mg is about two. Coffee also varies a lot by brew strength and cup size, so a large coffee-shop drip can match or beat any can. For a side-by-side of other drinks, see the caffeine in drinks chart.
Does sugar-free Red Bull have less caffeine?
No. Red Bull Sugarfree has the same caffeine as the original: 80 mg per 8.4 oz, 114 mg per 12 oz, 151 mg per 16 oz and 198 mg per 20 oz. Taking out the sugar doesn't change the caffeine. If you're switching to sugar-free to sleep better, the swap won't help with that part.
How much Red Bull caffeine is left at bedtime?
A small Red Bull at 4 PM leaves about 30 mg in you at 11 PM, and a 16 oz can at the same time leaves about 57 mg. The table uses the calculator's math: remaining caffeine = dose x 0.5^(hours / 5).
| Can at | 8.4 oz (80 mg) | 12 oz (114 mg) | 16 oz (151 mg) | 20 oz (198 mg) |
|---|---|---|---|---|
| 8 AM | 10 mg | 14 mg | 19 mg | 25 mg |
| 10 AM | 13 mg | 19 mg | 25 mg | 33 mg |
| Noon | 17 mg | 25 mg | 33 mg | 43 mg |
| 2 PM | 23 mg | 33 mg | 43 mg | 57 mg |
| 4 PM | 30 mg | 43 mg | 57 mg | 75 mg |
| 6 PM | 40 mg | 57 mg | 76 mg | 99 mg |
All values are for an 11 PM bedtime. This site uses about 25 mg at bedtime as a sensible ceiling. It isn't an official limit, but it's a useful line. A 16 oz can at 6 PM leaves about 76 mg at bedtime, almost as much as a fresh small can. Even a 20 oz can at 8 AM only just reaches the line by 11 PM.
What's the latest time to drink a Red Bull?
For an 11 PM bedtime, finish a small 8.4 oz Red Bull by about 2:37 PM and a 16 oz can by about 10:02 AM. Here's the cutoff for each size, so the can falls below 25 mg by bedtime:
| Bedtime | 8.4 oz | 12 oz | 16 oz | 20 oz |
|---|---|---|---|---|
| 10:00 PM | 1:37 PM | 11:03 AM | 9:02 AM | 7:04 AM |
| 10:30 PM | 2:07 PM | 11:33 AM | 9:32 AM | 7:34 AM |
| 11:00 PM | 2:37 PM | 12:03 PM | 10:02 AM | 8:04 AM |
| Midnight | 3:37 PM | 1:03 PM | 11:02 AM | 9:04 AM |
In hours before bed, that's about 8 h 23 min for the small can, 10 h 57 min for 12 oz, 12 h 58 min for 16 oz and 14 h 56 min for 20 oz. These are averages. If caffeine tends to linger for you, set the calculator to high sensitivity and the cutoffs move earlier. Pregnancy and some medications can slow clearance a lot.
Falling asleep fine doesn't mean the can had no effect. In an at-home sleep study, a large caffeine dose taken 6 hours before bed cut total sleep by more than an hour. For the hour-by-hour curve, read how long caffeine lasts.
How many Red Bulls 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 five small cans or about two and a half 16 oz cans, before you count any coffee, tea or soda.
Red Bull's own pages repeat the 400 mg daily figure and add that single doses up to 200 mg are considered safe for healthy adults, with 200 mg a day for pregnant and nursing women. The FDA notes that medical experts advise against energy drinks for children and teens. For the full daily picture, see how much caffeine is too much, and for how energy drinks compare with each other, see energy drinks and sleep.