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Caffeine Half-Life Calculator (300mg Dose)
Calculate exact caffeine decay and bed-time cutoff for 300mg caffeine dose.
Caffeine Half-Life & Sleep Cutoff (300mg)
Caffeine has a 5-6 hour half-life in healthy adults. Enter the time of your last cup:
People Also Ask (FAQs)
How long does 300mg of caffeine stay in your system?
After 5-6 hours, 150mg remains in your bloodstream. After 10-12 hours, roughly 75mg remains.