Caffeine Tracker
What's in your bloodstream, not how many cups.
01 · SETUP
Install it like an app
Android: Chrome, then ⋮ → Install app.
iPhone: Safari, then Share → Add to Home Screen.
Runs offline from then on.
02 · SETUP
Tell it about you
Weight, age, bedtime and half-life modifiers personalise the model. Set them once under Profile.
03 · USE
One tap to log
Tap a favorite. The curve shows the caffeine actually in your body, rising, peaking and fading.
04 · USE
Know your last call
The sleep cutoff is the latest coffee that still keeps you under 1.0 mg/L when you fall asleep.
05 · USE
Plan ahead
What if? checks a drink before you have it. Habits put your routine on the forecast.
08:00●●● ▮
meisdy.github.io/caffeine…⋮
Caffeine Tracker
A personal caffeine tracker that models what is actually in your bloodstream. No account. Nothing leaves your device.
Open the app
meisdy.github.io/caffeine…⋮
Caffeine in your body
0.00mg/LClear
Favorites
Today
Log
History
Insights
Profile
Install app?
Caffeine Tracker
meisdy.github.io
CancelInstall
About you
Half-life modifiers
Smokes
Uses oral contraceptives
Bedtime
Sleep threshold
Your half-life5.0 h
Today
Log
History
Insights
Profile
Caffeine in your body
0.00mg/LClear
Favorites
Espresso, work70 mg
Americano, work70 mg
Flat White2 shots
Black Tea250 ml
Caffeine curve
+70 mg · Espresso, work
Advice · Sleep cutoff
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Last coffee for a 23:00 bedtime. Later than that, you'd still be above 1.0 mg/L while falling asleep.
Today
Log
History
Insights
Profile
Planned today
Espresso, work
Mon–Fri · 10:00
LogSkip
What if?
Today
Log
History
Insights
Profile
Caffeine Tracker
Works offlineNo accountData stays on your device
meisdy.github.io/caffeine-tracker
Estimates from a population model. Not medical advice.