Caffeine Safe Limits: Calculate Your Safe Daily Dose

Enter your body weight to determine the safe amount of caffeine you can consume.

Your Weight

A safe caffeine limit is the amount of caffeine a person can consume without experiencing any caffeine overdose symptoms.

Determining a precise caffeine amount for everyone is challenging due to varying sensitivities and reactions based on age, medical history, and tolerance.

However, there is enough research available to make a recommendation based on an individual’s weight.

Caffeine amounts for healthy adults

For healthy adults with no medical issues, 300 mg – 400 mg of caffeine can be consumed daily without any adverse effects.¹

The calculator takes the medical recommendation and adjusts for your own body weight.

400 mg caffeine is equivalent to:


A review by the European Food Safety Authority concluded that a daily safe dose of 400 mg is safe for adults, and single doses of 200 mg at one time are fine for those engaging in exercise directly after the dose.

Based on the average human body weight worldwide7,  research concludes that 6 mg/kg (of body weight) is appropriate for those with normal sensitivity to the caffeine molecule.

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Safe caffeine limits for children

Because children’s brains are continuing to develop and their bodies are still growing, limited caffeine is recommended.

A study from The University Children’s Hospital in Zurich showed the importance of sleep for a child’s developing brain. Caffeine can interfere with sleep, possibly hindering proper brain development.

Ages 12 and under

Caffeine isn’t recommended for children under 12.

Occasionally, some doctors may recommend caffeine for children diagnosed with ADHD, but generally, there really is no reason for children under 12 to consume caffeine.

For children four or older, an occasional caffeinated soda or chocolate treat will likely pose no concern, and around 45 mg per day¹ is recognized as a safe amount, but caffeine should not be a daily part of a child’s diet.

Ages 13-18

Although it’s preferable to restrict caffeine intake for this age group, the growing pressures on teenagers from marketing, school, sports, and work have led to a rise in their caffeine consumption.

Developing teens should have no more than 100 mg of caffeine daily² due to the importance of sleep, brain development, and possibly unknown medical conditions.

This is equivalent to about:

  • 1.3 Shots of espresso
  • 1.25 8 fl oz Red Bulls
  • .5 of a 5 Hour Energy Shot
  • .6 of a 16 fl oz can of Monster Energy Drink
  • .2 of a Starbucks Venti brewed coffee
  • Three 12 fl oz  Cokes

The European Food Safety Authority recommends that for children ages 3-18; 3 mg of caffeine per kilogram of body weight seems safe (but cites that data is insufficient).

Example: A 44 lb / 20 kg child could safely consume 60mg of caffeine6.

Do you have any heart conditions?

Because caffeine is a stimulant, it increases heart rate as well as blood pressure. Therefore, those with heart arrhythmias³, murmurs, and hypertension should limit their caffeine intake.

Note that caffeine hasn’t been proven to cause arrhythmia, heart disease, or other heart-related problems.¹

Those with pre-existing arrhythmias, murmurs, and hypertension should limit caffeine to  200 mg daily and consult their physician before consuming caffeine.

Type 2 Diabetes

The majority of the research shows that caffeine doesn’t increase the risk of someone developing type 2 diabetes, but actually decreases risk.¹

However, those already diagnosed with type 2 diabetes should limit caffeine consumption because it can impair glucose metabolism in diabetics.4

Those with type 2 diabetes should restrict their consumption to 200 mg daily or follow their doctor’s instructions concerning caffeine intake.

Pregnant or nursing women

We have covered pregnancy and caffeine here.

Most experts agree that consuming 200 mg or less of caffeine a day equates to very little risk for the developing fetus and/or nursing infant.

200 mg of caffeine is equivalent to about:

  • 2.6 shots of espresso
  • 2.5 8 fl oz Red Bulls
  • One 5 Hour Energy Shot
  • .5 of a Starbucks Venti Brewed Coffee
  • 1.25 16 fl oz Monster energy drinks
  • Six 12 fl oz Cokes

Are you sensitive to caffeine?

For those ultra-sensitive to caffeine, it is hard to determine an exact limit.

Some people can have one cup of coffee (100 mg-120 mg) in the morning and still fail to get to sleep that evening. This is after the effects should have worn off (as it does for “normal” caffeine metabolizers).

If you choose to consume caffeine, do so in small amounts until you find the amount that works but doesn’t cause unwanted side-effects.

We suggest you start with 50 mg of caffeine daily and then slightly increase or decrease your consumption from there.

This is equivalent to about:

  • 1.5 12 fl oz Cokes
  • 1 4 fl oz brewed coffee. (not Starbucks)
  • 1 8 fl oz strong black tea
Need help with caffeine levels? Check out our list of caffeine amounts.



Any advice posted on our website is for informational purposes only and is not intended to replace any medical advice. Caffeine Informer makes no representations or warranties and expressly disclaim any and all liability concerning any treatment, action by, or effect on any person following the information offered through the website. If you have specific concerns or a situation arises in which you require medical advice, you should consult with an appropriately trained and qualified medical services provider.