How long Celsius lasts depends on the caffeine: a standard can has 200 mg, and with an average 5-hour half-life about 100 mg is still in your body 5 hours later and about 50 mg after 10 hours. It takes about 15 hours to drop below 25 mg, the level this site uses as a comfortable ceiling for bedtime. The buzz fades much sooner than that.
If you meant shelf life, check the date printed on the can; this page is about how long Celsius lasts in your body.
Free toolCaffeine Cutoff CalculatorHow much caffeine is still in you at bedtime, and your latest cup.How much caffeine is in a can of Celsius?
Celsius says its regular CELSIUS and CELSIUS Vibe drinks contain 200 mg of caffeine per can, and CELSIUS Essentials contain 270 mg per can. That's from the brand's own product facts page, checked on October 3, 2026. Its On-The-Go powder packets also list 200 mg, and its Hydration powders list none.
For comparison, an 8 oz cup of brewed coffee has about 95 mg, so one regular can is roughly two cups of coffee, and an Essentials can is closer to three. Recipes and lineups change, so the label on your can is the final word. To compare other drinks, see the caffeine in drinks chart.
How long does Celsius last in your system, hour by hour?
After one 200 mg can, about half is left at 5 hours, a quarter at 10, and an eighth at 15. This table uses the site's standard math: caffeine remaining = dose x 0.5^(hours / 5).
| Hours after drinking | 200 mg can | 270 mg can | Two 200 mg cans |
|---|---|---|---|
| 0 | 200 mg | 270 mg | 400 mg |
| 1 | 174 mg | 235 mg | 348 mg |
| 2 | 152 mg | 205 mg | 303 mg |
| 3 | 132 mg | 178 mg | 264 mg |
| 4 | 115 mg | 155 mg | 230 mg |
| 5 | 100 mg | 135 mg | 200 mg |
| 6 | 87 mg | 118 mg | 174 mg |
| 8 | 66 mg | 89 mg | 132 mg |
| 10 | 50 mg | 68 mg | 100 mg |
| 12 | 38 mg | 51 mg | 76 mg |
| 15 | 25 mg | 34 mg | 50 mg |
| 18 | 16 mg | 22 mg | 33 mg |
| 20 | 13 mg | 17 mg | 25 mg |
| 24 | 7 mg | 10 mg | 14 mg |
Time to drop below 25 mg: about 15 hours for 200 mg, 17 h 10 min for 270 mg, and 20 hours for two 200 mg cans.
The caffeine calculator runs the same math for your exact drink, time and sensitivity, and lets you stack a coffee or a second can on top.
How long does the energy from Celsius last?
The lift you feel tends to fade within a few hours, long before the caffeine is gone. That gap matters. When the buzz wears off, it's easy to assume the can is out of your system, but at 6 hours a 200 mg can still leaves about 87 mg, close to a full cup of coffee.
How fast you clear caffeine varies a lot between people. A major review of caffeine metabolism lists genetics, smoking, pregnancy, hormonal contraceptives, liver health and some medications as factors that speed it up or slow it down. If an afternoon can reliably keeps you up, assume you're on the slow side.
Latest time to drink Celsius before bed
For a 10:30 PM bedtime, finish a 200 mg can by about 7:30 AM, or a 270 mg can by about 5:20 AM, to be under 25 mg at bedtime. That's an early cutoff, and it's one of the honest trade-offs of a high-caffeine drink.
| Bedtime | Latest 200 mg can | Latest 270 mg can |
|---|---|---|
| 9:30 PM | 6:30 AM | 4:20 AM |
| 10:00 PM | 7:00 AM | 4:50 AM |
| 10:30 PM | 7:30 AM | 5:20 AM |
| 11:00 PM | 8:00 AM | 5:50 AM |
| Midnight | 9:00 AM | 6:50 AM |
The 25 mg line isn't an official limit. Plenty of people drink a can at noon and fall asleep fine. But falling asleep isn't the whole story: in an at-home sleep study, 400 mg of caffeine taken 6 hours before bed cut total sleep by more than an hour, and people generally didn't notice.
How much is left at bedtime if you drink it later?
A 200 mg can at noon leaves about 47 mg at a 10:30 PM bedtime; at 4 PM it leaves about 81 mg. Here's the full picture:
| Can of Celsius at | 200 mg can, left at 10:30 PM | 270 mg can, left at 10:30 PM |
|---|---|---|
| 8:00 AM | 27 mg | 36 mg |
| 10:00 AM | 35 mg | 48 mg |
| 12:00 PM | 47 mg | 63 mg |
| 2:00 PM | 62 mg | 83 mg |
| 4:00 PM | 81 mg | 110 mg |
An afternoon can leaves roughly a cup of coffee's worth of caffeine in you at lights-out. If you train after work, the same timing problem applies to any caffeinated drink; see how long pre-workout lasts and energy drinks and sleep.
How to fit Celsius around your sleep
- Make it a morning drink. If sleep matters, drink it with or soon after breakfast.
- One can, not two. Two 200 mg cans reach 400 mg, the FDA daily figure that Celsius's own facts page cites, before counting any coffee or tea.
- Count everything. Coffee, tea, soda and pre-workout all add to the same total.
- Afternoon slump? A 20-minute nap or a walk outside won't leave anything behind at bedtime.
- Work nights? Count back from when you'll actually sleep, not from 10:30 PM. The shift work sleep calculator gives you a caffeine cutoff around your shift.
If you notice a racing heart, chest pain or severe anxiety after caffeine, stop and get medical advice.