What time should you stop drinking coffee?
Short answer: about 8 hours before bed. If you wake up at 7:00 AM and want 7.5 hours of sleep, go to bed around 11:15 PM and have your last coffee by about 3:15 PM. Sensitive to caffeine? Stop 10 hours before bed instead.
| Wake up | Bedtime | Last coffee |
|---|---|---|
| 5:00 AM | 9:15 PM | 1:15 PM |
| 6:00 AM | 10:15 PM | 2:15 PM |
| 6:30 AM | 10:45 PM | 2:45 PM |
| 7:00 AM | 11:15 PM | 3:15 PM |
| 7:30 AM | 11:45 PM | 3:45 PM |
| 8:00 AM | 12:15 AM | 4:15 PM |
| 9:00 AM | 1:15 AM | 5:15 PM |
How the coffee cutoff works
Caffeine has a half-life of roughly five hours, so half of an afternoon latte is still in your system at dinner. A 2013 study in the Journal of Clinical Sleep Medicine (Drake et al.) found that caffeine taken six hours before bed still reduced total sleep by more than an hour, which is why the calculator starts from bedtime and works backwards.
Your bedtime comes from 90-minute sleep cycles plus about 15 minutes to fall asleep. Waking at the end of a cycle, rather than in the middle of one, is why some 7.5-hour nights feel better than 8.
Does decaf count?
Decaf still has a small amount of caffeine, usually a few milligrams per cup. For most people it's fine after the cutoff.
What about tea, soda and energy drinks?
They all contain caffeine. Black and green tea, colas, energy drinks and pre-workout should follow the same cutoff.
I fall asleep fine after coffee. Am I immune?
Falling asleep isn't the whole story. Caffeine can reduce deep sleep even when you don't notice it, so try the cutoff for a week and see how you feel.