buncha/health & fitness/caffeine

Caffeine Half-Life Calculator

Caffeine has an average half-life of 5 hours, but ranges from 1.5 to 9.5 hours depending on genetics, age, smoking, pregnancy, and medication. Adjust below.

Your half-life — 5.0 h50

1.5h (fast)5h (avg)9.5h (slow)

Today's caffeine intake

Planned bedtime

Total intake

95 mg

Peak level

95 mg

at 08:00

At bedtime

13 mg

Caffeine over time

08:00+15h14:00

Estimates only. Caffeine sensitivity varies. Pregnancy, medications, and health conditions can dramatically alter half-life.

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About Caffeine Half-Life Calculator

Track caffeine levels through the day. See when it will affect your sleep.

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