CALCULATOR 22
Caffeine Dosage Calculator
A pre-workout caffeine dose for your body weight, checked against safe limits.
Pre-workout dose
Enter your weight.
For general information only; not medical advice. Consult a qualified professional before making health decisions.
How this is calculated
Performance dose
3–6 mg per kg, about 60 min before exercise
Safe limits (healthy adults)
Up to 400 mg per day Up to 200 mg in one dose Pregnancy: up to 200 mg per day
Benefits start from about 2 mg/kg. Side effects like jitters, a racing heart and poor sleep become common from about 9 mg/kg.
Sources
- Guest NS et al. (2021), International Society of Sports Nutrition position stand: caffeine and exercise performance. J Int Soc Sports Nutr 18:1.
- EFSA Panel on Dietetic Products, Nutrition and Allergies (2015), Scientific opinion on the safety of caffeine. EFSA Journal 13(5):4102.
About the caffeine dosage calculator
How caffeine helps exercise
Caffeine blocks adenosine, a signal that builds up as you get tired, so effort feels easier. Studies show small but reliable gains in endurance, power and strength. Most benefit comes at 3–6 mg per kg of body weight, taken about an hour before training.
Read more about the Caffeine calculator
Staying within safe limits
For healthy adults, Europe's food safety authority considers up to 400 mg a day, and 200 mg in one go, to be safe. For anyone over about 67 kg, 6 mg/kg goes past 400 mg, so start at the low end. Caffeine lasts hours: a dose in the late afternoon can cut your sleep even if you fall asleep fine.
If you're pregnant, have a heart condition, high blood pressure or anxiety, or take medicines that interact with caffeine, ask your doctor what's right for you.
Frequently asked questions
How much caffeine should I take before a workout?
3–6 mg per kg of body weight about an hour before. For a 70 kg person that's 210–420 mg; start at the low end.
How much caffeine is in a coffee?
An espresso has about 80 mg and a 200 ml cup of filter coffee about 90 mg, but brands vary a lot.
Will I get used to caffeine?
Daily users still benefit, though the effect may be a bit smaller. Raising the dose to chase it adds side effects faster than benefit.