Sleep calculator / Caffeine limit
Caffeine Limit Calculator
How much caffeine can you have today? Pick who it's for, tally your drinks, and see your daily limit, your total so far and what's left.
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Used for the EFSA ceiling of 3 mg per kg of body weight a day. Stays on this device.
Caffeine so far today
How much caffeine can I have a day?
For most healthy adults, up to 400 mg a day, according to both the U.S. Food and Drug Administration and the European Food Safety Authority (EFSA). That's about four 8 oz cups of brewed coffee. Lower limits apply in pregnancy and for children and teens.
| Who | Daily limit | Source |
|---|---|---|
| Healthy adults | Up to 400 mg a day; single doses up to 200 mg | FDA, EFSA |
| Pregnant | Under 200 mg a day | ACOG, EFSA |
| Breastfeeding | Up to 200 mg a day | EFSA |
| Teens (12 to 18) | Up to 3 mg per kg of body weight; no energy drinks | EFSA, AAP |
| Children (under 12) | 3 mg per kg is a ceiling, not a target; none under age 2 | EFSA, AAP, FDA |
The FDA also says that if you're pregnant, trying to become pregnant or breastfeeding, you should talk to your health care provider about whether you need to limit caffeine.
How the calculator works
It adds up the caffeine in the drinks you enter, compares the total with the daily limit for the group you pick, and shows what's left. For teens and children it multiplies body weight in kilograms by 3 mg, the level EFSA proposed for habitual intake in children and adolescents, and never goes above the adult 400 mg.
Caffeine in common drinks
| Drink | Caffeine |
|---|---|
| Brewed coffee, 8 oz | about 95 mg |
| Espresso, 1 oz shot | about 63 mg |
| Black tea, 8 oz | about 47 mg |
| Coca-Cola, 12 oz can | 34 mg |
| Red Bull, 8.4 oz can | 80 mg |
| Monster Energy, 16 oz can | 160 mg |
Coffee, espresso and tea are averages from USDA data, and real cups vary a lot. Soda and energy drink figures come from the makers. More detail: caffeine in espresso, caffeine in Coke, Red Bull, Monster, or the full caffeine in drinks chart.
Caffeine for children and teens
The American Academy of Pediatrics says the caffeine and other stimulants in energy drinks have no place in the diet of children and adolescents. The FDA notes that federal dietary guidelines say to avoid caffeinated drinks under age 2. EFSA's figure of 3 mg per kg of body weight a day is the most it considered safe for habitual intake, so treat it as an upper ceiling rather than an amount to aim for. For a 30 kg (66 lb) child that's 90 mg; for a 60 kg (132 lb) teen, 180 mg.
Under the limit can still mean poor sleep
The daily limit is about health, not sleep. Caffeine has an average half-life of about 5 hours, so an afternoon coffee well inside 400 mg can still be in you at bedtime. Find the latest time for your drink with the caffeine cutoff calculator, or read how much caffeine is too much for sleep.
When to ask a doctor
These limits are for healthy people. Heart conditions, high blood pressure, anxiety, and some medications can make caffeine affect you more strongly, or change how fast your body clears it. If any of those apply, or you're pregnant, ask your doctor or pharmacist what's right for you. This calculator is general information, not medical advice.
Frequently asked questions
How much caffeine can I have a day?
Most healthy adults can have up to 400 mg a day, according to the FDA and EFSA. That is about four 8 oz cups of brewed coffee. Pregnant people should stay under 200 mg, and children and teens need much less.
How much caffeine is safe at one time?
EFSA found that single doses up to 200 mg, about 3 mg per kg of body weight, do not raise safety concerns for healthy adults. That is roughly two 8 oz cups of coffee.
How much caffeine can I have while pregnant?
Under 200 mg a day. ACOG says moderate intake below 200 mg does not appear to be a major factor in miscarriage or preterm birth, and EFSA uses the same figure. Check with your own provider.
How much caffeine can a teenager have?
EFSA proposed up to 3 mg per kg of body weight a day for children and adolescents, which is 180 mg for a 60 kg (132 lb) teen. The American Academy of Pediatrics says energy drinks have no place in a teen's diet.
Is 400 mg of caffeine too much?
Not for most healthy adults: the FDA says 400 mg a day is not generally associated with negative effects. People who are sensitive to caffeine, pregnant, or on certain medications may need less.
Sources
- U.S. Food and Drug Administration. Spilling the beans: how much caffeine is too much?
- EFSA Panel on Dietetic Products, Nutrition and Allergies. Scientific opinion on the safety of caffeine. EFSA Journal, 2015;13(5):4102.
- European Food Safety Authority. Caffeine (topic summary of the 2015 opinion).
- American College of Obstetricians and Gynecologists. Committee Opinion No. 462: Moderate caffeine consumption during pregnancy, 2010.
- American Academy of Pediatrics, Committee on Nutrition and Council on Sports Medicine and Fitness. Sports drinks and energy drinks for children and adolescents: are they appropriate? Pediatrics, 2011.
- U.S. Department of Agriculture. FoodData Central: coffee, brewed (FDC 171890); espresso (FDC 171891); black tea, brewed (FDC 173227).
- The Coca-Cola Company. What is caffeine? (Coca-Cola 34 mg per 12 oz).
- Red Bull. How much caffeine is in a can of Red Bull Energy Drink? (80 mg per 8.4 fl oz).
- Monster Energy. Monster Energy original green (160 mg caffeine per 16 fl oz).
Related reading
- How Much Caffeine Is in a 5-hour Energy Shot? Regular and Extra StrengthA Regular Strength 5-hour Energy shot has 200 mg of caffeine and Extra Strength has 230 mg, in a 1.93 oz bottle. See what's left at bedtime.4 min read
- How Much Caffeine Is in a Dunkin' Iced Coffee? Small, Medium and LargeDunkin' lists about 196 mg of caffeine in a small iced coffee, 294 mg in a medium and 392 mg in a large. See what's left at bedtime and your cutoff.5 min read
- How Much Caffeine Is in Alani Nu? Energy Drink, Witch's Brew and Mini CansA 12 oz Alani Nu energy drink has 200 mg of caffeine, Witch's Brew included. The 8.4 oz mini has 100 mg. See what's left at bedtime and your cutoff.4 min read
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These results are general estimates, not medical advice. Everyone's sleep is a little different. If you're often exhausted despite enough time in bed, snore loudly, or have been told you stop breathing in your sleep, see a doctor.