Caffeine Cutoff Calculator
Find the best time to stop drinking coffee so caffeine is less likely to disrupt deep sleep tonight.
Uses caffeine half-life to estimate when only about 25% remains at bedtime.
Common caffeine amounts
| Drink | Caffeine | Relative load |
|---|---|---|
| Cold brew, 16 oz | ~240mg | |
| Espresso, double | ~150mg | |
| Drip coffee, 8 oz | ~95mg | |
| Energy drink | ~80mg | |
| Black tea | ~47mg | |
| Green tea | ~29mg |
Caffeine cutoff questions this calculator answers
Many people can fall asleep after coffee but still lose deep sleep. This page targets practical searches like “what time should I stop drinking coffee,” “how long does caffeine stay in your system,” and “does afternoon coffee affect sleep.”
Choose your bedtime and sensitivity level to estimate a safer last-caffeine window based on half-life, not a generic one-size-fits-all rule.
Some people clear caffeine slowly and need a longer cutoff. If you wake at night or feel wired at bedtime, use the sensitive setting.
Late caffeine can reduce slow-wave sleep even when sleep onset feels normal, which is why morning grogginess can trace back to afternoon coffee.
A 5.5-hour half-life means roughly 25% can remain after 11 hours. The calculator turns that biology into a usable daily cutoff.
Have a non-medical caffeine tracker, wellness app, sleep habit template, or educational resource? Request a reviewed partner placement. We confirm fit before payment and label sponsored mentions clearly. View partner options.