Sleep & Recovery

Caffeine Half-Life

How much caffeine is still in your system at bedtime.

Inputs
150 mg
10100250500
5 h
25810
Standard is 5h. Slow metabolizers: 7–9h. Fast: 3–4h. Pregnancy + some meds extend it.
In your system
19mg at bedtime
Hours from drink to bed
15.0h
% remaining at bedtime
13%
Reaches < 10 mg at
Threshold below which most people don't notice sleep impact.
+19.5 h
Decay over the next 16 hours
3 mg56 mg109 mg163 mg+0h+3.5h+7h+10.5h+14h+16hmg

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