buncha.tools
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.

Like every tool on Buncha, this one runs entirely in your browser. There's no upload, no log, no record of what you've pasted or generated. Close the tab and the data is gone.

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