Your Dose
Comparison: Fast vs Slow
Enter your dose to see how fast and slow metabolizers process the same amount of caffeine.
Clearance Timeline
Saved Sessions
Your calculated sessions are saved automatically.
See how long caffeine stays in your system. Compare fast vs slow CYP1A2 metabolizers side by side.
Enter your dose to see how fast and slow metabolizers process the same amount of caffeine.
Your calculated sessions are saved automatically.
Caffeine clearance follows first-order kinetics: the amount remaining halves every 2.5 hours (fast), 5 hours (average), or 9 hours (slow). The formula is C(t) = C₀ × 0.5^(t/t½), where t½ is your metabolizer-type half-life.
Enter your dose, consumption time, and select your CYP1A2 metabolizer status. The tracker plots a 24-hour clearance curve and shows when you drop below 50mg and 25mg thresholds — critical for sleep planning.
• Fast metabolizers: half-life ~2.5h. Slow: ~9h.
• If you don't know your type, start with Average.
• The 50mg threshold is when sleep becomes easier.
• Compare Fast vs Slow side-by-side to see the genetic gap.