For healthy adults, up to 400 mg of caffeine a day is considered safe (FDA/EFSA), and the performance-studied pre-workout dose is 3–6 mg/kgtaken 30–60 min before training. Enter your weight for your personal numbers — and count coffee, tea and energy drinks toward the daily total.
Enter your weight for your pre-workout dose and safe daily ceiling.
Up to about 400 mg a day is considered safe for most healthy adults (FDA and EFSA), with any single dose kept at or below ~200 mg if you are sensitive. Count all sources — coffee (~95 mg a cup), tea, energy drinks and pre-workout. Pregnant people are advised to stay under ~200 mg/day.
The performance-studied range is 3–6 mg per kg of body weight, taken about 30–60 minutes before training. For a 175 lb (80 kg) person that is roughly 240–480 mg — start at the low end to gauge tolerance, and remember it still counts toward your daily ceiling.
Jitteriness, a racing heart, anxiety, upset stomach and disrupted sleep are the common signs you have had too much or too late in the day. Caffeine has a long half-life (~5–6 hours), so a late-afternoon dose can still hurt your sleep. Cut back if you notice these.
General information, not medical advice. Caffeine tolerance and safe limits vary with health conditions, medication and pregnancy — talk to a clinician if unsure.