Know your peak.
Skip the crash.
Log a coffee. See when you'll be sharpest, when the crash hits, and how late is too late.
The caffeine timing protocol
Stop guessing your cutoffs. Learn how caffeine metabolism varies by beverage, how to pair L-theanine for calm focus, and how to gently reset your tolerance over 14 days. Backed by 12 published sleep and metabolism studies.
- Personal cutoff hours. Find your last-sip time based on bedtime and drink dose.
- Smooth focus. The 2:1 L-theanine ratio and hydration rules to help avoid jitteriness.
- Printable reference sheet. A 6-page guide with milligram tables and technical diagrams for your desk.
Where should we send it?
Includes a 7-day Stimly PRO trial in the App Store.
How it works
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1
Take a short quiz
Weight, age, and how coffee actually hits you. That tunes the curve to your body.
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2
Log your drinks
From your favorites, our database, or a barcode scan. A cold brew sipped over two hours behaves differently than a quick espresso.
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3
Read your curve
See when you're at your sharpest, when the crash starts, and how much caffeine will still be around at bedtime.
Straight from the app
Free to start
Free Tier
- Personal caffeine curve, calculated live
- Sleep readiness projection for tonight
- Body Signals: Tag jitters, focus, or crashes directly on your curve
- Daily limits & drink logging
Stimly PRO
- Adaptive Tolerance Engine (4 adaptation tiers)
- Long-term energy trends & 30/90-day history
- Exportable PDF Wellness Reports & Barista Tools
The core tracker, personal archetype, and body signal logging are free forever. PRO unlocks the adaptive tolerance engine, long-term trends, and PDF wellness reports.
Stay in your sweet spot
Available on the App Store for iOS.