Calculate My Blood Alcohol Level

Blood Alcohol Concentration Formula:

\[ BAC = \frac{Alcohol (g)}{Weight (kg) \times r} - (Metabolism \times Time) \]

Alcohol (g):

grams

Weight:

Gender:

Metabolism Rate:

g/L/hr

Time:

hours

Blood Alcohol Concentration (BAC):

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1. What is Blood Alcohol Concentration?

Blood Alcohol Concentration (BAC) is a measure of the amount of alcohol in your bloodstream. It's expressed as a percentage that represents grams of alcohol per 100 milliliters of blood. BAC is used to determine legal intoxication levels and assess impairment.

2. How Does the Calculator Work?

The calculator uses the Widmark formula:

\[ BAC = \frac{Alcohol (g)}{Weight (kg) \times r} - (Metabolism \times Time) \]

Where:

\( Alcohol \) — Total grams of alcohol consumed
\( Weight \) — Body weight in kilograms
\( r \) — Gender constant (0.68 for males, 0.55 for females)
\( Metabolism \) — Alcohol metabolism rate (typically 0.015 g/L/hr)
\( Time \) — Hours since first drink

Explanation: The formula estimates how alcohol distributes in body water and subtracts the amount metabolized over time.

3. Understanding BAC Levels

Details:

0.00-0.05%: Mild impairment
0.05-0.08%: Significant impairment (illegal to drive in many jurisdictions)
0.08-0.15%: Seriously impaired
0.15-0.30%: Severe impairment
Above 0.30%: Potentially life-threatening

4. Using the Calculator

Tips: Enter alcohol consumed in grams (1 standard drink ≈ 14g), your weight in kg, select gender, and input time since drinking began. The default metabolism rate of 0.015 g/L/hr is average but can vary.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this calculator?
A: This provides an estimate only. Actual BAC can vary based on metabolism, food intake, medication, and individual differences.

Q2: What is a standard drink?
A: Typically 14g of pure alcohol: 12oz beer (5%), 5oz wine (12%), or 1.5oz spirits (40%).

Q3: How long does it take to sober up?
A: The body metabolizes alcohol at about 0.015% per hour. Nothing speeds up this process significantly.

Q4: Can I drive after drinking?
A: Never drive if you feel impaired. Legal limits vary by jurisdiction (typically 0.05-0.08%), but impairment begins at lower levels.

Q5: Why is the gender constant different?
A: Women typically have less body water and different enzyme activity, leading to higher BAC from the same amount of alcohol.