Blood Alcohol Calculator (BAC) — Italian Legal Limits

Italy has a zero-tolerance policy for new drivers (licence held < 3 years), drivers under 21, and professional drivers (bus, taxi, truck): 0.0 g/L. For other drivers the limit is 0.5 g/L (Art. 186 Codice della Strada). Penalties escalate sharply: 0.5–0.8 g/L is a fine + licence suspension; above 0.8 g/L is a criminal offence.

BAC (g/L) = [Alcohol consumed (g) / (Body weight (kg) × r)] − (Elimination rate × Hours elapsed). Where r = 0.68 for men, 0.55 for women (Widmark distribution factor). Elimination rate ≈ 0.15 g/L/hour. This is a theoretical estimate — actual BAC varies significantly with individual metabolism.

Italy uses a standard drink (Unità Alcolica, UA) of 12 g of pure ethanol: a 200ml glass of wine at 12% ABV = ~19g alcohol, a 33cl beer at 5% ABV = ~13g, a 40ml shot of spirits at 40% ABV = ~13g, an Aperol Spritz (60ml Aperol + 90ml Prosecco) ≈ 20g. The calculator converts ABV + volume to grams of alcohol automatically.

The liver eliminates alcohol at approximately 0.10–0.15 g/L per hour — roughly one standard drink per hour for an average adult. The rate does not increase with coffee, cold showers, food or exercise. Only time eliminates alcohol. A BAC of 0.8 g/L requires approximately 5–6 hours to reach zero.

Italian law (D.Lgs. 159/2016) places a duty of care on bar and restaurant owners for responsible alcohol service. Understanding BAC helps staff recognise visibly intoxicated customers, avoid over-serving, and reduce liability. The CCNL Pubblici Esercizi also requires training on responsible alcohol service for HoReCa workers.

No BAC calculator is accurate. The Widmark formula gives a theoretical estimate that can differ from actual BAC by ±20–30%. Factors like food intake, medications, fatigue, health conditions and individual metabolism all affect alcohol absorption. This tool is for educational purposes only. Never drive after consuming alcohol.