Frequently asked questions

Calcohol is an iOS app that helps you log alcoholic drinks and see an estimated blood alcohol content (BAC) curve over time. Unlike typical trackers that plot a curve but assume instant drinks and fixed absorption, Calcohol models drink duration, fed vs. empty stomach timing, and elimination minute by minute.

Many BAC apps plot a curve over time using the Widmark formula, but they usually assume each drink is consumed instantly and don't adjust absorption for whether you've eaten recently. That misses a big part of real-world BAC behavior: a 12 oz beer might take five minutes or an hour to finish, and food can significantly delay your peak. Calcohol runs a time-based simulation — modeling drink duration, fed vs. empty stomach absorption, overlapping drinks, and elimination — so your estimate reflects where you are now, not just a simplified projection.

Calcohol has no in-app purchases or subscriptions. Check the App Store listing for the current price, if any.

You must be of legal drinking age in your country or region and comply with all applicable local laws and regulations. On first launch, the app asks you to confirm that you meet this requirement. The App Store may display an age rating (such as 18+) based on alcohol-related content, but that rating does not replace the legal drinking age where you live.

Calcohol uses published pharmacokinetic models (Widmark equation with BMI-adjusted factors, linear absorption, and constant elimination). Results are estimates only — individual metabolism varies based on genetics, food, medications, hydration, and other factors. See our methodology page for details.

No. Never rely on Calcohol as a substitute for a breathalyzer, responsible judgment, or legal advice. Do not drive or operate machinery if you have been drinking, regardless of what the app shows.

No. Calcohol is for informational purposes only. It is not a medical device and does not provide medical or legal advice. Always make safe decisions independently of the app.

Weight (lbs), height (inches), and sex at birth. These are used in the Widmark-based BAC model. You can update them anytime from the profile button in the app.

Food slows gastric emptying, which delays alcohol absorption. Calcohol uses a longer time-to-peak (90 min vs. 45 min) when you indicate you’ve eaten recently, producing a more realistic rising BAC curve.

Most Widmark-based apps plot a curve but assume each drink enters your bloodstream all at once and use the same absorption timing whether or not you've eaten. In reality, you sip over minutes or hours — and that spread changes when your BAC rises and peaks. Calcohol distributes each drink's alcohol across its estimated consumption duration (from your logged finish time, timing relative to the next drink, or drink size) and adjusts time-to-peak for fed vs. empty stomach, producing a much more realistic curve.

Tap the + button, enter ABV (%), size in fluid ounces, whether you’ve eaten, and the drink time. Presets for beer, wine, shots, and cocktails help you get started quickly.

Swipe left on a drink in the list to edit or delete it. Swipe right to mark a drink as finished if you’re still consuming it over time.

Green (< 0.04), amber (0.04 – 0.08), and red (≥ 0.08) are visual guides based on common reference thresholds. They are not legal limits — laws vary by jurisdiction.

Yes. Use the Day / Week / Month / Year picker at the top of the main screen, along with the arrow buttons to move between time ranges.

Yes. Calcohol supports iPhone and iPad in portrait orientation.

No. Your profile and drink history are stored locally on your device in a private SQLite database. Nothing is uploaded to Calcohol servers.

No. Calcohol has no sign-in, no accounts, and no cloud sync.

No. Calcohol does not include third-party analytics, advertising SDKs, or cross-app tracking.

Delete the Calcohol app from your device. Because data is stored locally, uninstalling removes your profile and drink history. See the full privacy policy for details.