See your BAC live
A colour-coded ring updates as alcohol is absorbed and cleared, with a personal low–high range and a warning while it's still rising.
New Live Activities, widgets & iPad
Know your BAC.
Know your BAC.
Pace your night.
Wake up proud.
Alco Nut is your smart drinking companion. It estimates your blood alcohol in real time, tells you exactly when you'll be sober, and helps you build healthier habits — no judgement, no account.
- Free on iPhone & iPad
- No account needed
- Private by design
Why Alco Nut
A good night out shouldn't come with guesswork
"Am I okay?" "When will this wear off?" "How much did I actually drink this week?" Alco Nut answers the questions everyone asks — clearly, privately, in a tap.
Know when you're sober
Clock times for "sober at" and "under the legal limit", plus notifications when you get there — so you can plan the morning with confidence.
Log in one tap
Favourites, recent drinks, half portions and undo. Log from the dashboard, a widget, the Lock Screen or Siri — even later in the night.
Build better habits
Dry-day streaks, weekly goals and savings in drinks, calories and money help you cut back at your own pace — no lectures.
How it works
Set up in 30 seconds. Useful all night.
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Tell it about you
Weight, sex, age and activity level personalise the estimate. Pick your country's legal limit and preferred BAC unit — %, ‰ or mg/100 mL.
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Log what you drink
Tap a favourite, search the drinks database, or add your own craft beer. Sipping slowly or had dinner? Alco Nut accounts for both.
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Follow your curve
Watch your BAC curve and projection, get notified when you're under the limit and when you're sober. Your week adds up in Insights.
Features
Everything you need. Nothing you don't.
Smart BAC engine
More realistic than a basic BAC calculator
Most calculators assume every drink hits your blood instantly. Alco Nut simulates your night minute by minute.
- Absorption over time — BAC rises gradually, and more slowly after food.
- Sipping counts — a drink you nurse for an hour is spread across that hour.
- Personal body model — uses your height and age when available for a tighter estimate.
- Curve & projection — see your peak, when you'll be under the limit, and when you'll hit zero.
Fast, forgiving logging
Logging that keeps up with the night
If logging is slow, it doesn't happen. Alco Nut is built for one hand, low light and the occasional mistake.
- Quick Add — your favourites and recent drinks, one tap away. Hold for half, double or "15 minutes ago".
- Undo & edit — fix the size, strength or time of any drink, or delete it.
- Forgot a night? — add it from History or the calendar and your stats stay accurate.
- Real glass sizes — pints, cans, shots and bottles, plus spend tracking if you want it.
Habits & insights
Cut back without the guilt trip
Mindful drinking is about awareness, not perfection. Alco Nut celebrates progress and keeps your history honest.
- Dry-day streaks & calendar — late nights count toward the right day, not split at midnight.
- Weekly goals — standard drinks and dry days. Changing a goal never rewrites past weeks.
- What you've saved — drinks, calories and money compared with your own baseline.
- Trends & milestones — weekly charts, top drinks, busiest days and badges to unlock.
Beyond the app
Your BAC, right where you look
Check in without unlocking your phone, or log a round without leaving the conversation.
Live Activity on your Lock Screen
A live countdown to sober, your estimated BAC, drink count and a "Same again" button — updated through the night.
Dynamic Island
Your BAC and sober time stay visible while you use other apps. Expand it to log another drink.
Widgets & Siri
BAC, Quick Log and Dry Days widgets for the Home and Lock Screen. Or just ask Siri.
"Log an IPA in Alco Nut"
Logged IPA. Peak around 0.052.
"What's my BAC in Alco Nut?"
Screenshots
Beautiful in every light
Twelve themes, light and dark. Swipe through the app.
Free BAC calculator
Estimate your BAC in seconds
A simplified version of the engine inside Alco Nut. Add your drinks and see an estimated BAC and when you'd be sober.
Buzzed
0.000
Estimated BAC %
Sober in—
Under your limit—
Estimate only. Everyone metabolises alcohol differently. Never use this or any app to decide whether you can drive. Get the full engine in Alco Nut — with sipping time, your height and a live curve.
Make it yours
Themes, colours & a buddy with personality
Pick a vibe — try it on this page
Alco Nut ships with light and dark themes like Classic, Midnight, Ocean, Ember, Forest and Rose, plus a custom colour picker. Tap one to recolour this site.
Meet your Drink Buddy
An animated 3D companion — the acorn, a Viking, a pirate, a professor and more — that reacts to your night, raises toasts from around the world and shares tips like "alternate with water".
"Here's to the friend who knows your story and still wants to have a drink with you!"
iPhone & iPad
Room to see your whole night
On iPad, Alco Nut spreads out: your BAC, curve, drinks and habits side by side.
Privacy & safety
Your nights are your business
No sign-up, no social feed, no selling your data. Just a helpful companion that looks out for you.
No account, ever
Your profile and history stay on your device. Nothing to register, nothing to forget.
Optional iCloud & backups
Turn on sync to use your private iCloud across iPhone and iPad, or export a backup file any time.
Apple Health, if you like
Optionally save standard drinks and BAC estimates to the Health app alongside the rest of your wellbeing.
FAQ
Questions, answered
How accurate is the BAC estimate?
Alco Nut uses the Widmark method extended with an absorption model: alcohol enters your blood gradually, more slowly after food, and is eliminated at a steady hourly rate. It personalises the estimate with your weight, sex, age, height and activity level and shows a low–high range. It is still an estimate — individual metabolism varies — and it must never be used to decide whether you can drive.
Is Alco Nut free?
Yes. Alco Nut is free to download and use, with no subscription. You can optionally support development by treating your Drink Buddy with a tip.
Do I need to create an account?
No. There is no sign-up. Your profile and history live on your device. You can optionally turn on iCloud sync, which uses your own private iCloud database.
Can I log drinks without opening the app?
Yes. Use the Quick Log widget on your Home Screen, the Same again button on the Live Activity and Dynamic Island, or ask Siri to log a drink. Widgets also show your BAC and when you'll be sober.
I forgot to log a drink. Can I add it later?
Yes. Log a drink with an earlier time, edit or delete any drink, or add a whole past night from History or the dry-day calendar. BAC and peaks are recalculated automatically.
Can Alco Nut help me drink less?
Alco Nut includes dry-day streaks, a calendar of dry and drinking days, weekly goals for standard drinks and dry days, milestones, and an estimate of drinks, calories and money saved compared with your own baseline. Goals are stored per week, so changing a goal never rewrites past weeks.
Which BAC units and legal limits are supported?
You can show BAC as a percentage (0.08), per mille (0.8‰) or milligrams per 100 mL (80). You choose your country's legal limit during setup and can change it any time.
Does Alco Nut work on iPad?
Yes. Alco Nut runs on iPhone and iPad and uses the larger iPad screen with multi-column layouts.
Is Alco Nut a medical or breathalyzer device?
No. Alco Nut provides estimates for information and entertainment only. It is not a medical device or breathalyzer and is not for legal use. If you have been drinking, don't drive.
Enjoy the night.
Know where you stand.
Download Alco Nut free for iPhone and iPad. Set up in 30 seconds — no account, no strings.
Download on theApp Store
Contact
We'd love to hear from you
Feature idea, a drink missing from the database, or something not working? Send us a note.