Standard drink BAC Calculator: Alcohol & Calories per Drink

Standard drink: Alcohol content, strength and type of drink.

Alcohol refers to fermented and distilled beverages. Its rich history spans millennia, globally crafted and integral to human cultures and social traditions since ancient times.

In terms of calories, a 355 ml / 12 ounces of standard drink contains about 120 calories. Of those, approximately 98 come from the alcohol content alone. The remaining 22 calories are derived primarily from sugars and carbohydrates present in the drink.

A standard drink contains 355 ml / 12 ounces with an alcohol percentage of 5%. In terms of raw alcohol, this means a standard drink contains 14 grams of alcohol.

A standard drink equals about 1.00 standard drinks according to NIAAA guidelines.

Compared to other drinks, a standard drink is roughly equivalent to:

1.00 bottles of beer (355 ml / 12 oz) (American size)
0.71 bottles of beer (500 ml / 16.9 oz) (European size)
1.00 glasses of wine (150 ml / 5 oz)
1.00 shots of hard spirits (tequila, whisky, vodka etc.) (45ml / 1.5 oz)

Although there is significant variation, the human body metabolizes about 5 to 7.5 grams of alcohol per hour.

This means it can take a healthy adult anywhere between 2 to 3 hours to metabolize the 14 grams of alcohol in just one standard drink.

Methodology

Click to expand our BAC calculator methodology

This calculator uses the standard version of the Widmark formula to produce the BAC estimate.

A common version is: BAC = [Alcohol (g) / (Body weight (g) x r)] x 100

Alcohol (g): The mass of pure alcohol consumed.
Body weight (g): The person's weight.
r: The Widmark factor, a gender-specific constant for body water (typically 0.68 for males and 0.55 for females).

To account for alcohol elimination over time, a rate (β) is subtracted:

BAC = [Alcohol (g) / (Body weight (g) x r)] x 100 – (Hours x β)

Hours: Time passed since drinking started.
β (beta): The elimination rate, averaging 0.015% per hour.

Effects by Blood Alcohol Concentration

Below are the effects of different levels of Blood Alcohol Concentration, based on the guidelines of the USA's National Highway Traffic Safety Administration.

BAC %	Behavior	Impairment
0.001–0.029	Mild relaxation, otherwise normal.	Subtle; minor loss of coordination.
0.030–0.059	Mild euphoria, lowered inhibitions.	Reduced alertness and judgment.
0.060–0.099	Buzzed, over-confident, exaggerated emotions.	Impaired reasoning, vision, and reaction time.
0.100–0.199	Drunk, boisterous, or sloppy.	Major motor impairment; slurred speech.
0.200–0.299	Dazed, confused; blackouts likely.	Needs help walking. Nausea/vomiting.
0.300–0.399	Stupor; likely loss of consciousness.	Critical; little comprehension. Bladder control lost.
0.400–0.500	Coma; unconscious.	Life-threatening; breathing and heart rate suppressed.
>0.50	Unconscious.	Potentially fatal; high risk of complete respiratory failure.

Frequently Asked Questions

How many servings of standard drink does it take to get drunk?

As a general estimate, an average 80kg / 176lb man may feel drunk (defined as 0.08% BAC or more) after around 4 servings of standard drink. An average 70kg / 154 lb woman might feel drunk and reach 0.08% BAC after about 3 servings of standard drink. These are rough estimates and not guarantees.

How much alcohol is in a standard drink?

A typical standard drink has an alcohol by volume (ABV) of 5%, which is about 14 grams of alcohol.

Is a standard drink considered a standard drink?

According to the NIAAA's guidelines, a standard drink contains 14 grams of alcohol. A 355 ml / 12 ounces standard drink with an ABV of 5% typically contains 14 grams of alcohol, so it is considered a standard drink

Can you get drunk off one standard drink?

Most people do not experience strong impairment from a single standard drink, but some may notice light effects depending on their tolerance, metabolism, and body weight.

DISCLAIMER: The BAC calculator is meant for educational purposes only. As per the guidelines of the Center for Disease Control, alcohol is a substance that can severely impact your health, so exercise caution. The BAC calculator and information generated from it is not intended to replace the medical advice of your doctor or health care provider and should not be relied upon; nor do the BAC calculator or information generated from it constitute legal advice. Please consult your healthcare provider for advice about a specific medical condition and legal counsel for any legal questions. There is no blood alcohol calculator that is 100% accurate because of the numerous factors and complexities relating to alcohol consumption by of different individuals. In addition to the gender, body weight and amount of alcohol consumed in a time period, blood alcohol content of any individual person is influenced by that person’s metabolism, health issues, medications taken, history of alcohol consumption and the amount of food and non-alcoholic beverages eaten before or during alcohol consumption, among other factors. The best that can be done is a rough estimation of the BAC level based on known inputs.

Our medical reviewers have verified the educational content and confirmed that the calculator correctly implements the standard BAC estimation algorithms. Note that individual results vary significantly. This is an educational estimate only.