Caffeine Calculator: Know Your Daily Coffee Intake Limit
The dose makes the poison. This common expression refers to the fact that even healthy things can be harmful when consumed incorrectly. You can die from drinking too much water or get sick or overeating kale.
Caffeine is no exception, and the right amount provides numerous proven health benefits. But take too much, and you’ll find yourself anxious, jittery, or worse.
Use this handy daily caffeine calculator to determine your ideal caffeine intake and how much of your favorite brew you should consume to stay safe.
Home Grounds’ Daily Caffeine Calculator
There are 70 to 140 mg of caffeine in an 8-oz cup of regular black coffee and the FDA recommends no more than 400 mg of caffeine daily for a healthy adult. This means that an average person can only have 3 to 4 cups of regular coffee per day. Still, the precise number of that limit will vary with age, gender, body weight, and genetics. While we can’t account for inherited caffeine sensitivity, this caffeine daily limit calculator offers a good idea of how much of your favorite style of coffee is healthy for you.
You should bookmark this article if you find this caffeine overdose calculator useful.
What is Caffeine?
Caffeine is a stimulant that acts on the central nervous system. It occurs naturally in tea, coffee, cacao, and other plants. Or it can be prepared synthetically and added to products like caffeine pills, caffeinated sodas, and energy drinks.
Learn more in this informative video from beloved coffee expert James Hoffmann:
Caffeine Health Benefits
Caffeine offers numerous health benefits when consumed appropriately, especially when you drink coffee. According to the Harvard School of Public Health, coffee has many other nutrients that work symbiotically with caffeine to promote overall health.
Consumption of 3 to 5 standard cups of coffee daily has been consistently associated with a reduced risk of several chronic diseases.
Caffeine’s main impact is on your brain. It boosts energy by blocking the neurotransmitter adenosine, which is responsible for making you feel sleepy. Studies have also shown that it can improve focus and mood and protect against brain diseases like Alzheimer’s and Parkinson’s (1).
Outside the brain, caffeine has been shown to boost metabolism, protect against heart disease and diabetes, improve athletic performance, and reduce the risk of liver damage, among other possible benefits. Talk about a miracle drug – in the right dose, that is.

Caffeine Overdose
Coffee overdose to the point of illness or death is very rare. If you exceed our caffeine counter’s recommended dose, you might notice mildly unpleasant symptoms like anxiety, restlessness, and trouble sleeping. Go further over the limit, and you could suffer from migraines, an irregular heartbeat, or increased blood pressure. At very high doses, vomiting, abdominal pain, and seizures are possible.
Death By Caffeine
Studies have shown that caffeine blood levels need to reach about 180 mg/L to run the risk of death (2). That’s equivalent to drinking about 30 cups of coffee in a short time frame!
Overdose in caffeine is usually the result of caffeine pills or amped-up energy drinks.
For example, there’s the case of 29-year-old personal trainer Tom Mansfield, who died after accidentally consuming caffeine powder equivalent to 200 cups of coffee (3).
Final Thoughts
Knowing your daily caffeine limit and the amount of coffee it takes to get there is essential, and this caffeine calculator makes it easy. Caffeine is a powerful force for good in your body when consumed correctly, but take too much, and you’ll experience jittery discomfort.
If you found this calculator useful, share it with your coffee and tea-loving friends to reap the health benefits of proper caffeine consumption together.
FAQs
The pregnancy caffeine limit is 200 mg daily, about half the standard guideline. In the past, pregnant women were advised to avoid caffeine altogether because it can cross the placenta. But more recent research has shown that moderate amounts are safe.
It takes up to 10 hours for caffeine to wear off – i.e., completely clear your bloodstream. However, in only six hours, 50% of the caffeine consumed will be metabolized, at which point only those sensitive to caffeine will still feel its effects.
The coffee style with the most caffeine is espresso, which has 60 – 80 mg per ounce. However, espresso is typically consumed in small volumes, no more than 3 ounces at a time. 16-ounce drip coffee or cold brew can easily have more caffeine than a double shot.
References
- Petre, A. (2020, June 3). What Is Caffeine, and Is It Good or Bad for Health? Retrieved from https://www.healthline.com/nutrition/what-is-caffeine
- Jones, A.W. (2017, February). Review of Caffeine-Related Fatalities along with Postmortem Blood Concentrations in 51 Poisoning Deaths. Journal of Analytical Toxicology. 41(3). Retrieved from https://www.researchgate.net/publication/315611897_Review_of_Caffeine-Related_Fatalities_along_with_Postmortem_Blood_Concentrations_in_51_Poisoning_Deaths
- Rettner, R. (2022, March 4). Man dies from caffeine overdose after drinking equivalent of 200 cups of coffee. Retrieved from https://www.livescience.com/caffeine-overdose-200-cups-of-coffee