SafeBAC CalculatorInformational BAC Tool

BAC Calculator for Women: By Weight & Drink Type - SafeBAC

Biological differences mean alcohol affects women differently than men. Use this tool to understand your estimated levels.

Estimate your BAC

Enter your details and drinks to see an approximate blood alcohol concentration. Results are only estimates and must not be used to decide if you can drive.

Use an approximate value if you are not sure. The estimate is sensitive to body weight.

This helps us compare your estimated BAC with commonly cited legal limits in your selected region.

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minutes

Count from the first sip of your first drink. The longer you have been drinking, the lower your BAC may be from metabolism.

Drinks you have consumed

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Never use BAC estimates to decide whether you can drive.

Estimated BAC and safety overview

These numbers are only rough estimates. Everyone processes alcohol differently.

Fill in your details and drinks, then select “Estimate BAC” to see estimated values and safety guidance.

Why alcohol affects women differently

Even if a woman and a man have the same body weight and drink the same amount, the woman will typically have a higher Blood Alcohol Concentration (BAC). This is primarily due to physiology, not tolerance.

Body water percentage

Alcohol is water-soluble. Women naturally have a lower percentage of body water (about 49-52%) compared to men (about 58%). This means the same amount of alcohol is dissolved in less water, resulting in a higher concentration.

Metabolic enzymes

Women often have lower levels of alcohol dehydrogenase (ADH), the enzyme that breaks down alcohol in the stomach before it reaches the bloodstream. As a result, more alcohol is absorbed into the blood.

Hormonal factors

Fluctuations in hormone levels during the menstrual cycle can also affect alcohol metabolism, causing intoxication to occur faster at certain times of the month.

Explore more tools:

Female BAC FAQ

Generally, yes. Due to lower total body water and different enzyme levels, women reach a higher BAC faster than men from the same number of drinks.
Yes. Having less body mass (specifically less water volume) means alcohol will be more concentrated in your system. Losing weight typically lowers your alcohol tolerance.
No. The legal limit (e.g., 0.08% or 0.05%) is the same for all drivers regardless of sex. However, women will likely reach that limit with fewer drinks than men.