Alcohol elimination: The 0.015% Rule

How long does alcohol stay in your system? Map the elimination curve.

Elimination Case Study: Tracking 2 glasses of wine for a 65kg female after 4 hours.

Your Variables

x

Assumes ~( 13-20g ) ethanol per drink.

Your Results

Your Alter Ego

The Ice Breaker 🧊

Tonight's State: Noticeable buzz

You’re warmer, louder, and suddenly everyone is interesting.

Typical behavior: telling stories, laughing more, meeting strangers

0.70‰

Theoretical Peak BAC

If all alcohol was consumed instantly.

0.55‰

End of Drinking BAC

Concentration when you took your last sip.

0.00‰

Current Blood Alcohol Concentration

Your estimated concentration right now.

BAC Projection

Metabolism Rate: -0.15‰ / h

📱 Phone Risk Indicator

🤔CAUTION
010033

You've opened your contacts list at least twice. For research purposes, obviously.

How likely are you to ruin a relationship right now?

Recovery Blueprint

Universal Recommendations

Electrolyte drink
Light carbohydrates
Gentle walk
Avoid more alcohol

Hangover Forecast

Your Alter Ego

The Ice Breaker 🧊

Theoretical Peak BAC

0.00‰

Hangover Risk

48%

Share Your Results

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Methodology

Calculations are based on the standard Widmark formula: BAC = (Total Alcohol Grams / (Weight × r)) × 0.1 - (0.015 × Hours Since Last Drink) where r depends on gender, combined with a weighted penalty model factoring in dehydration, sleep deficit, and drinking speed to estimate subjective hangover severity. Example: A 75kg male drinking two 500ml beers (5% ABV = 40g alcohol) hits ~0.80‰. Factoring in metabolism, it drops to ~0.50‰ after 2 hours.

The 0.015% BAC Per Hour Standard

Alcohol metabolism is a linear process. Unlike many other substances, the liver processes ethanol at a constant rate regardless of its concentration in the blood.

The 0.015% BAC Per Hour Standard

On average, the human body eliminates 0.015% BAC (approx. 0.15‰) per hour. While genetic factors (like ADH and ALDH enzymes) can cause slight variations, this rate is remarkably consistent across populations.

The Role of Gastric Emptying

Food in the stomach slows down gastric emptying, delaying the 'dumping' of alcohol into the small intestine where most absorption occurs. This leads to a lower, later peak BAC compared to drinking on an empty stomach.

The Metabolism Curve Explained

Your BAC doesn't drop the moment you stop drinking. There is an absorption lag where alcohol continues to enter the bloodstream from the stomach and small intestine. Peak BAC usually occurs 30–90 minutes after the last sip.

Read Next

Widmark Formula: The Science of BAC

Understand the math behind Blood Alcohol Concentration estimation.