Know when your
caffeine clears.
Track your caffeine intake and see exactly when it leaves your system. Half-life science meets simple design.
Free · No account required See it in action.
Know Your Caffeine 
See the Decay Curve 
Log Any Drink 
Sleep Better 
Widget Caffeine, understood.
Half-Life Decay Visualization
Watch your caffeine levels decay in real-time. Our beautiful chart shows exactly how much caffeine is in your system right now and when it will be gone.
Quick-Log Presets
Log your caffeine in seconds. Tap preset buttons for espresso, coffee, tea, energy drinks, and more. Custom amounts when you need them.
Clear-By Time
The "Clear By" time tells you when caffeine will drop below 20mg — effectively out of your system. Perfect for planning your last coffee before bed.
HealthKit Sync
Automatically sync your caffeine intake to Apple Health. Track alongside your sleep and other health data to see the full picture.
Widgets
Home Screen and Lock Screen widgets show current caffeine level and clear-by time at a glance. Always know where you stand.
Completely Offline
No servers, no cloud sync, no network requests. Your caffeine data stays on your device. Period.
5.7 hours.
That's the average half-life of caffeine. Every 5.7 hours, half the caffeine in your system is metabolized away.
We use this to calculate exactly how much caffeine remains in your system at any moment — so you can make smarter decisions about when to drink (and when to stop).
Track your caffeine.
Free on the App Store. No account required.
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