Blood Alcohol Calculator

Blood Alcohol Content (BAC) Calculator

Male Female
1 drink = 12oz Beer (5%), 5oz Wine (12%), or 1.5oz Shot (40%)

Estimated BAC Level: 0.00%

Understanding Your BAC (Blood Alcohol Content)

Blood Alcohol Content (BAC) is a metric used to measure the amount of alcohol in a person's bloodstream. It is expressed as a percentage. For example, a BAC of 0.08% means that there are 0.08 grams of alcohol for every 100 milliliters of blood.

How is BAC Calculated?

This calculator uses the Widmark Formula, which is the standard scientific method for estimating alcohol concentration. The formula considers several variables:

  • Alcohol Consumed: The total amount of pure ethanol in grams.
  • Body Weight: Heavier individuals have more water in their bodies to dilute alcohol.
  • Gender: Men and women metabolize alcohol differently due to differences in body water composition and enzymes.
  • Time: The body typically metabolizes alcohol at a rate of 0.015% per hour.

What Defines a "Standard Drink"?

In the United States, a standard drink contains approximately 14 grams of pure alcohol. This is generally found in:

  • 12 ounces of regular beer (about 5% alcohol).
  • 5 ounces of wine (about 12% alcohol).
  • 1.5 ounces of distilled spirits (about 40% alcohol).

BAC Levels and Effects

BAC Range Typical Effects
0.02% – 0.03% Slight relaxation, loss of shyness, lightheadedness.
0.04% – 0.06% Feeling of well-being, relaxation, minor impairment of reasoning.
0.07% – 0.09% Impaired balance, speech, and vision. Legal driving limit (0.08%).
0.10% – 0.12% Significant motor impairment and loss of judgment.
Disclaimer: This calculator is for informational purposes only and provides an estimate. Your actual BAC can be affected by factors like metabolism, hydration, food intake, and health status. Never drink and drive. If you have been drinking, please use a designated driver or ride-sharing service.
function calculateBAC() { var genderRatio = parseFloat(document.getElementById('bac_gender').value); var weightLbs = parseFloat(document.getElementById('bac_weight').value); var drinks = parseFloat(document.getElementById('bac_drinks').value); var hours = parseFloat(document.getElementById('bac_hours').value); var resultBox = document.getElementById('bac_result_box'); var output = document.getElementById('bac_output'); var status = document.getElementById('bac_status'); var warning = document.getElementById('bac_warning'); if (isNaN(weightLbs) || isNaN(drinks) || isNaN(hours) || weightLbs <= 0) { alert("Please enter valid positive numbers for weight, drinks, and time."); return; } // Widmark Formula // BAC = [Alcohol consumed in grams / (Body weight in grams * r)] * 100 – (Time * 0.015) // 1 standard drink = 14 grams // 1 lb = 453.592 grams var alcoholGrams = drinks * 14; var weightGrams = weightLbs * 453.592; var rawBAC = (alcoholGrams / (weightGrams * genderRatio)) * 100; var metabolismLoss = hours * 0.015; var finalBAC = rawBAC – metabolismLoss; if (finalBAC = 0.08) { resultBox.style.backgroundColor = '#ffd1d1'; status.innerHTML = "LEGALLY IMPAIRED (In most jurisdictions)"; status.style.color = "#b22222"; warning.innerHTML = "You are above the legal driving limit of 0.08%. Do not operate a motor vehicle."; } else if (finalBAC > 0.04) { resultBox.style.backgroundColor = '#fff9d1'; status.innerHTML = "SIGNIFICANT IMPAIRMENT"; status.style.color = "#856404"; warning.innerHTML = "Reaction times and judgment are likely affected. It is unsafe to drive."; } else if (finalBAC > 0) { resultBox.style.backgroundColor = '#d1ffd1'; status.innerHTML = "SLIGHT IMPAIRMENT"; status.style.color = "#155724"; warning.innerHTML = "You are under the typical legal limit, but alcohol may still affect your performance."; } else { resultBox.style.backgroundColor = '#e2e3e5'; status.innerHTML = "SOBER / NEGLIGIBLE BAC"; status.style.color = "#383d41"; warning.innerHTML = "Alcohol has likely been metabolized."; } }

Leave a Comment