Caffeine Clock

Stop guessing why you can't sleep. Caffeine Clock uses advanced half-life modeling to show you exactly how much caffeine is still in your system—long after your last cup. Most people don't realize that up to 25% of their morning coffee is still active at bedtime. Caffeine Clock visualizes this hidden energy, helping you find your perfect "cutoff time" for better rest and consistent focus. KEY FEATURES: Real-Time Half-Life Graph See your active caffeine decline hour by hour. Know exactly when you'll be clear. Smart Sleep Alerts Get notified if a late latte puts your sleep at risk. We calculate the impact based on your personal bedtime. Personalized Metabolism Everyone processes caffeine differently. Customize your half-life sensitivity to match your body. Focus vs. Jitter Zones Stay in the productive "Focus Zone" and avoid the anxiety-inducing "Wired Zone" with clear visual thresholds. Live Widgets Monitor your status right from your Home Screen and Lock Screen without opening the app. WHY CAFFEINE CLOCK? Free: No paywalls, no subscriptions. Private: All data stays on your device. No accounts, no tracking. Simple: Just tap to log. We handle the math. Take control of your daily rhythm. Download Caffeine Clock today and sleep better tonight.