Caffeine Calculator

Add your daily caffeine sources — coffee, tea, energy drinks, soda — and see your total against the FDA's safe limit of 400mg/day for healthy adults. Also shows your personalized limit by body weight.

400mg/day is the widely cited safe upper limit for healthy adults. Pregnancy, anxiety disorders, heart conditions, and certain medications lower this threshold significantly. Caffeine has a half-life of ~5–6 hours.