# Blood Alcohol Content (BAC) Estimator Estimate your BAC from sex, weight, drinks and time using the Widmark formula. Returns g/dL and ‰, predicts sober time, and flags the impairment tier and legal driving limits. > Canonical page: https://elysiatools.com/en/tools/bac-calculator - **Category:** Health - **Keywords:** bac calculator, blood alcohol content, bac estimator, widmark formula, alcohol metabolism, sober time, drink driving limit, standard drink ## Overview The Blood Alcohol Content (BAC) Estimator calculates your estimated blood alcohol concentration using the Widmark formula based on your sex, body weight, alcohol consumption, and elapsed time. It provides results in both g/dL and permille (‰), estimates the time required to return to a sober state, and flags impairment levels alongside legal driving limits. ## Inputs - **Sex** (select) - **Body weight** (number): e.g. 75 - **Weight unit** (select) - **Input mode** (select) - **Standard drinks (14g ethanol each)** (number): e.g. 3 - **ABV (%)** (number): e.g. 13 - **Volume per drink (mL)** (number): e.g. 150 - **Number of drinks** (number): e.g. 3 - **Hours since first drink** (number): e.g. 2 - **Decimal places** (number) ## When to use - When you want to estimate your blood alcohol concentration after consuming standard drinks or custom beverages over a specific timeframe. - When you need to understand how long it might take for your body to metabolize alcohol and reach a sober state. - When comparing your estimated BAC against common legal driving limits and impairment thresholds for safety awareness. ## How it works - Select your sex and enter your body weight in kilograms or pounds to establish your body water constant. - Input your alcohol intake by choosing either standard drinks (14g of ethanol each) or entering custom beverage details including volume, ABV, and quantity. - Specify the hours elapsed since your first drink to account for the body's natural alcohol metabolism rate. - Submit the details to calculate your current BAC in g/dL and ‰, view your impairment tier, and see the estimated time to sobriety. ## Use cases - Estimating personal BAC levels after a social gathering to gauge impairment and understand alcohol clearance times. - Educating individuals on how body weight, sex, and drink strength affect blood alcohol concentration. - Comparing the metabolic differences between consuming standard drinks versus custom high-ABV craft beers. ## Frequently asked questions ### What formula does this calculator use to estimate BAC? It uses the Widmark formula, which factors in sex, body weight, alcohol dose, and elapsed time to estimate blood alcohol concentration. ### What is considered a standard drink in this tool? A standard drink is defined as containing 14 grams of pure ethanol, which is the standard measure in the United States. ### Can I input custom drinks with specific ABV and volume? Yes, switch the input mode to custom to enter the exact alcohol by volume (ABV) percentage and volume in milliliters. ### Does this estimator guarantee I am safe to drive? No, this tool provides a mathematical estimate for educational purposes only and cannot replace actual breathalyzer or blood tests. ### How does the tool calculate alcohol clearance over time? 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