HalfCaff
Real-Time Body Caffeine Level
Free · In-App Purchases · Designed for iPad. Not verified for macOS.
Track your body's caffeine level in real time using half-life science. Know exactly how much more you can drink before bed. 70+ drink presets included.
HalfCaff tracks your caffeine intake and shows exactly how much caffeine is in your body right now.
Using scientifically-based half-life calculations, HalfCaff answers the one question every coffee lover asks: "Can I have another cup and still sleep tonight?"
"○○mg remaining" — Based on your bedtime threshold and the FDA daily limit (400mg), see exactly how much more you can drink at a glance.
Features:
- Real-time body caffeine level with circular gauge
- Remaining allowance display ("○○mg OK to drink")
- 24-hour caffeine decay curve
- 70+ drink presets (Starbucks, Doutor, Tully's official data)
- Home screen widgets (Small & Medium)
- Dynamic Island & Live Activities
- Personalized half-life based on your caffeine sensitivity
HalfCaff Pro unlocks:
- Home screen widgets
- Dynamic Island display
- Unlimited history
Includes a 3-day free trial.
Terms: https://halfcaff.decoy284.net/terms/
Privacy Policy: https://halfcaff.decoy284.net/privacy/
Ratings & Reviews
- This app has not received enough ratings or reviews to display an overview.
- Improved App Store metadata for better discoverability
The developer, Yutaro Koide, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Provider
- Yutaro Koide
- Size
- 4.1 MB
- Category
- Health & Fitness
- Compatibility
Requires iOS 17.0 or later.
- iPhone
Requires iOS 17.0 or later. - iPad
Requires iPadOS 17.0 or later. - Mac
Requires macOS 14.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
9+
- 9+
- Contains
Health or Wellness Topics
- In-App Purchases
Yes
- Monthly USD 6.99
- Yearly USD 29.99
- Weekly USD 1.99
- Copyright
- © 2026 Yutaro Koide
