Caffeine Intake Tracker Calculator
Add up your caffeine sources over the day (coffee, tea, energy drinks...), compare the total to the recommended 400 mg/day limit, and estimate how much is still active in your system based on the time elapsed since each intake.
Caffeine content varies with preparation: roughly 80-100 mg for an espresso or a drip coffee, 30-50 mg for black tea, 80-160 mg for a can of energy drink.
How it works
This tool adds up the caffeine (in mg) from each entry you provide to get your daily total, then compares it to the 400 mg/day threshold generally used for a healthy adult. It also estimates the caffeine still 'active' in your body by applying a decline based on an average half-life of 5 hours: the initial amount of a dose is halved every 5 hours that pass.
Where does the 400 mg per day limit come from?
It's a benchmark commonly cited by health authorities (such as EFSA in Europe) for a healthy, non-pregnant adult. This limit does not apply to pregnant or breastfeeding women, teenagers, or people sensitive to caffeine, for whom lower limits are recommended.
Why does 'active' caffeine decrease over time?
Caffeine is gradually eliminated by the liver. Its half-life generally ranges from 3 to 7 hours depending on the individual (metabolism, pregnancy, smoking, medications...); this calculator uses an average value of 5 hours as an indication. The result is a general estimate, not a precise individual measurement.
This tool is for information only and is not a substitute for the advice of a healthcare professional, especially in case of pregnancy, heart problems, sleep disorders or known caffeine sensitivity.
The calculation runs entirely in your browser: no data you enter is sent to a server.