Caffeine cutoff
Caffeine cutoff
The latest you can have caffeine without it affecting tonight's sleep.
Last cup of coffee at
12:00 PM
Caffeine has a 5.5-hour half-life. After this time, enough remains in your system to disrupt sleep architecture even if you fall asleep on schedule.
Half-life varies by genetics, age, pregnancy, and certain medications (especially SSRIs and oral contraceptives, which slow caffeine metabolism). If you're sensitive, push the cutoff 2 hours earlier.