Caffeine Curfew Calculator
Protect your sleep! Caffeine has a half-life of 5-6 hours, meaning half of it is still in your system long after you finish your drink. This tool helps you determine if you're leaving enough time between your last coffee and bedtime.
Excellent! A gap of 9.6 hours is ideal for preserving sleep quality.
How Caffeine Affects Your Sleep
Caffeine is a powerful stimulant that works by blocking adenosine, a neurotransmitter that promotes sleepiness. When you drink coffee, tea, or an energy drink, caffeine binds to adenosine receptors in your brain, making you feel alert and awake. However, this process disrupts your natural sleep-wake cycle. Even if you manage to fall asleep, the quality of your sleep can be significantly reduced. Caffeine can decrease deep sleep, the most restorative stage of sleep, leaving you feeling groggy and unrefreshed the next day. The general recommendation is to stop consuming caffeine at least 8 to 10 hours before your intended bedtime to allow your body to metabolize it and prepare for restful sleep.
Understanding Caffeine Half-Life
The half-life of a substance is the time it takes for the amount of that substance in your body to be reduced by half. For caffeine, the average half-life in healthy adults is about 5 to 6 hours. This means if you consume 200mg of caffeine (roughly one strong cup of coffee) at 4 PM, you will still have 100mg in your system at 9 PM. By 2 AM, you'd still have 50mg circulating. This lingering caffeine is often enough to interfere with your ability to fall asleep and stay asleep, highlighting the importance of a caffeine curfew.
Disclaimer
This tool provides general guidance and is for educational purposes only. Individual responses to caffeine can vary based on genetics, metabolism, and tolerance. This is not a substitute for professional medical advice.