How long does caffeine last?
The half-life of caffeine is about 5 hours for most adults, meaning half of it is still in your system 5 hours later.
Calculator
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Analysis
Interpretation of the current calculator output
Enter values to see detailed analysis and insights.
How to Use
Step-by-step instructions
- 1Enter your body weight (kg).
- 2Select the type of coffee.
- 3Enter the number of cups.
- 4The calculator will estimate your caffeine dose and effects.
Dosage Calculation
Calculates the caffeine dosage relative to body weight to estimate physiological effects.
Dose (mg/kg) = Total Caffeine / Body WeightVariables:
Drip Coffee~95mgEspresso~63mgExample
Morning Coffee
Inputs:
Weight:70 kg
Type:Drip
Cups:2
Steps:
- 1.Total = 2 * 95 = 190 mg
- 2.Dose = 190 / 70 = 2.7 mg/kg
Result:
Focused & Awake