Caffeine in drinks
How much caffeine is in Energy drink?
Data checked against the source on 2026-10-03 by Oleksii Y.
One 250 ml can of Energy drink has 80 mg of caffeine, according to European Food Safety Authority.
How Energy drink compares
- Strength: 32 mg per 100 ml.
- One 250 ml can has as much caffeine as about three quarters of a cup of brewed coffee, which has 94.8 mg per 8 fl oz cup.
How much will be left at bedtime?
1 × 250 ml can of Energy drink
Left at 11:00 PM (8 h later), average metabolism
≈ 26 mg
Range 13–40 mg (fast to slow metabolism)
To be at 50 mg or less by bedtime, have 80 mg by 6:52 PM (average) or 4:50 PM (slow metabolism).
What sleep studies found near this dose
- Gardiner et al. 2025 (randomized trial): In 23 healthy young men, 100 mg taken 12, 8 or 4 hours before bed had no significant effect on measured or self-rated sleep.
- Gardiner et al. 2023 (meta-analysis): To avoid losing sleep time, the authors suggest a coffee (107 mg per 250 ml) at least 8.8 hours before bed.
Estimate from a simple model: half-life of 3, 5 or 8 hours, 50 mg bedtime target. How we calculate
Caffeine by size
| Serving | Caffeine |
|---|---|
| 250 ml can | 80 mg |
| 12 fl oz can (some brands) | 41–246 mg |
| 16 fl oz can | 54–328 mg |
How long does Energy drink stay in your system?
Our model halves caffeine every 5 hours for average metabolism, and every 3 or 8 hours for fast or slow metabolism. From one 250 ml can of Energy drink (80 mg), about 40 mg is still in your body 5 hours later and about 20 mg after 10 hours. If you clear caffeine slowly (an 8-hour half-life), about 34 mg is left after 10 hours.
Estimated caffeine left at 11:00 PM from one 250 ml can (80 mg), using a half-life of 5 hours for average metabolism and 3 to 8 hours for the range. How we calculate
| Had at | Left at bedtime (average) | Range |
|---|---|---|
| 8:00 AM (15 h before bed) | ≈ 10 mg | 3–22 mg |
| 12:00 PM (11 h before bed) | ≈ 17 mg | 6–31 mg |
| 3:00 PM (8 h before bed) | ≈ 26 mg | 13–40 mg |
| 6:00 PM (5 h before bed) | ≈ 40 mg | 25–52 mg |
How many fit in a day?
Reference amounts are for caffeine from all sources combined. Counted at the upper end of the stated amount, one serving at a time:
- Up to 400 mg a day for most healthy adults (FDA, EFSA): about 5 servings.
- Up to 200 mg at one time for healthy adults (EFSA): about 2 servings in one go.
- Up to 200 mg a day in pregnancy (EFSA, NHS): about 2 servings.
These are reference amounts for groups of people, not a personal limit. Some people feel jittery or sleep worse on much less. See the cutoff calculator for timing.
Good to know
EFSA's 80 mg figure for a 250 ml can is based on the most popular brand, at 320 mg per liter.
Energy drink vs other energy drink drinks
- CELSIUS Energy Drink: Energy drink has less caffeine than CELSIUS Energy Drink per 12 fl oz can (some brands): 41–246 mg vs 200 mg.
- Alani Nu Energy Drink: Energy drink has less caffeine than Alani Nu Energy Drink per 12 fl oz can (some brands): 41–246 mg vs 200 mg.
- GHOST Energy: Energy drink has about the same amount of caffeine as GHOST Energy per 16 fl oz can: 54–328 mg vs 200 mg.
- PRIME Energy: Energy drink has about the same amount of caffeine as PRIME Energy per 16 fl oz can: 54–328 mg vs 200 mg.
Common questions
How much caffeine is in Energy drink?
European Food Safety Authority gives 80 mg of caffeine per 250 ml can. Other sizes are in the table on this page.
How many Energy drink servings can I have in a day?
The FDA and EFSA cite up to 400 mg of caffeine a day, from all sources combined, for most healthy adults. At 80 mg per 250 ml can, that is about 5 servings if Energy drink is your only source. In pregnancy the reference is 200 mg a day.
How late can I drink Energy drink?
With an 11:00 PM bedtime, our model suggests having one serving by about 6:52 PM for average metabolism, or 4:50 PM if you clear caffeine slowly. This is an estimate, not a rule.
How long does Energy drink stay in your system?
Of the 80 mg in one 250 ml can, roughly 40 mg remains after 5 hours and 20 mg after 10 hours with our average 5-hour half-life. From fast to slow metabolism, 10 hours later it is between 8 and 34 mg.
Where the number comes from
- Caffeine (topic page). European Food Safety Authority. Table "How much caffeine is there in…", row "A standard can of 'energy drink' (250ml) | 80mg" Accessed 2026-10-02. Source ↗
- Spilling the Beans: How Much Caffeine Is Too Much? U.S. Food and Drug Administration. Energy drinks: "54 to 328 milligrams of caffeine per 16 fluid ounces, with a few brands containing 41 to 246 milligrams of caffeine per 12 fluid ounces" Accessed 2026-10-02. Source ↗
Recipes and labels change. If a number here no longer matches the label, the label wins.
General information, not medical advice
If you feel unwell after caffeine — for example chest pain, a fast or irregular heartbeat that does not settle, fainting, confusion or trouble breathing — get urgent medical help. If you are pregnant or breastfeeding, under 18, take medication, or have a heart, liver or anxiety condition, high blood pressure or a sleep disorder, ask a doctor or pharmacist what amount is right for you.
Sources
- U.S. Food and Drug Administration (2024). Spilling the Beans: How Much Caffeine is Too Much? FDA Consumer Updates. fda.gov ↗
- European Food Safety Authority. Caffeine | EFSA. EFSA topic page (summary of the 2015 Scientific Opinion on the safety of caffeine). efsa.europa.eu ↗
- NHS. Foods to avoid in pregnancy. NHS. nhs.uk ↗
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