Caffeine Tracking

Caffeine Tracking

Beanstats can estimate how much caffeine each brew contains, track what is still in your system, and write it to Apple Health.

Every number here is an estimate. Real caffeine content varies a lot with the bean, the grind, and your technique, so treat these figures as a guide rather than a measurement.

Enabling

Turn on Settings > Features > Caffeine Tracking. Beanstats asks for permission to write to Apple Health, and a Caffeine section appears in the sidebar.

From then on, every brew you save is estimated and logged automatically. Decaf beans are skipped.

The Caffeine Dashboard

Open Caffeine from the sidebar for the full picture:

CardDescription
In SystemCaffeine still active right now
TodayTotal consumed since midnight, turning red past your limit
At BedtimeProjected level when you plan to go to sleep
Daily LimitThe limit you set

Below the cards:

  • A sleep impact note based on the bedtime projection: unlikely to affect sleep under 50mg, may affect sleep for some between 50 and 100mg, likely to reduce sleep duration above that
  • A Caffeine Over Time chart showing the decay curve through your day, with markers for now and bedtime. Tap the magnifier to switch between the day view and the full decay
  • Today’s Caffeine, a timeline of each drink with its estimate

Caffeine logged to Apple Health by other apps is folded into these numbers too, so an energy drink or a tea counts toward your day.

How Estimates Work

Home Brews

Caffeine is worked out from your dose: dose in grams × rate per gram. Defaults come from published research (USDA, EFSA, and comparative extraction studies):

MethodDefault rate18g dose
Espresso7.0 mg/g~126 mg
Filter / Pour-over7.0 mg/g~126 mg
AeroPress7.0 mg/g~126 mg
French Press6.0 mg/g~108 mg
Moka Pot8.0 mg/g~144 mg
Cold Brew7.0 mg/g~126 mg

Your brew method name is matched against this list. Anything unrecognised falls back to the espresso or filter rate depending on the brewing style.

Cafe Brews

Cafe brews don’t record a dose, so fixed estimates per drink are used:

DrinkEstimate
Espresso, Macchiato, Cortado63 mg
Cappuccino, Latte, Flat White, Americano, Mocha126 mg
Pour Over, Chemex, Siphon, AeroPress95 mg
French Press95 mg
Cold Brew150 mg
Moka Pot130 mg
Turkish Coffee80 mg
Other95 mg

Decay

What is left in your system is modelled with a half-life: after one half-life, half of a dose is gone, after two, a quarter, and so on. The default half-life is five hours.

Caffeine Settings

Reachable from Settings > Features > Caffeine Settings once tracking is on.

SettingDescriptionDefault
BedtimeUsed for the bedtime projection and sleep impact note23:00
Daily limitYour target ceiling in mg400 mg
Metabolism SpeedFast (3h), Normal (5h), Slow (7h), or Very Slow (9h) half-lifeNormal
Home Brew RatesPer-method mg per gram, adjustable to match your setupSee above

Most healthy adults sit around a five-hour half-life. Smokers process caffeine faster, and people on oral contraceptives slower. Reset to Defaults restores the research-based rates.

Apple Health

Each brew writes a dietary caffeine sample stamped with the brew time and the method name:

  • Editing a brew updates its sample
  • Deleting a brew removes it
  • Decaf brews never write a sample
  • If you decline Health permission, brews still save normally and caffeine logging quietly does nothing

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