Wellness

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计算器: Blood Alcohol Calculator (BAC).

使用计算器: Blood Alcohol Calculator (BAC)，根据输入获得清晰实用的结果。

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01

Set your values

Results update as you type.

Gender
Drink Type
Estimated BAC
4.455%
StatusIncreased Impairment (Lowered coordination)
Estimated Hours to Sober (0.00% BAC)3 hours
0.08% BAC referenceEstimate is below 0.08%
Disclaimer: This calculator provides an estimate based on average metabolic rates. Do not rely on this calculator to determine your fitness to drive. Always designate a sober driver.

FAQs

What is the Widmark formula?

The Widmark formula estimates BAC based on total alcohol consumed, body weight, gender, and metabolism over time.

What is the legal BAC limit for driving in the US?

In all US states (except Utah at 0.05%), the legal BAC limit for drivers 21 and older is 0.08%.

How fast does the body metabolize alcohol?

The human body metabolizes alcohol at an average rate of 0.015% BAC per hour.

Authoritative Source & Methodology
Reviewed: 2026-07-20

Source: NHTSA Widmark Formula & Alcohol Impairment Guidelines (US / International)

Reviewer: Mathify content team

Notice: Estimates blood alcohol concentration for educational purposes only. Individual metabolism, food intake, and tolerance vary. Never drive under the influence.

Cite this calculator

Canonical URL: https://mathify.one/zh/wellness/bac

Cite as: Mathify. (2026). 计算器: Blood Alcohol Calculator (BAC). https://mathify.one/zh/wellness/bac

Use Cases

Estimate sobriety after a night out

Use the calculator to get an idea of when your BAC might return to zero, helping you plan safe transportation or rest.

Example: After 3 drinks, the calculator might show you need 5 hours to reach 0.00%.

Understand legal driving limits

Check if your estimated BAC is above the legal driving limit, reinforcing the importance of not driving under the influence.

Example: Enter your details to see if your BAC is over 0.08%.

Frequently Asked Questions

How does the Blood Alcohol Calculator estimate BAC?
It uses the Widmark formula, which considers your weight, gender, number of drinks, and time elapsed to estimate your blood alcohol concentration. The result is an approximation, not a precise measurement.
What does 'legal driving status' mean in this calculator?
It indicates whether your estimated BAC is above or below the typical legal limit for driving (0.08% in most US states). It is for informational purposes only and should not be used to decide if you are safe to drive.
How is the time to return to 0.00% BAC calculated?
It estimates the time needed for your body to metabolize alcohol until your BAC reaches zero, based on an average elimination rate. Individual metabolism varies, so this is only an estimate.

Tips & Common Mistakes

Tips

  • Enter your weight accurately, as it significantly affects the BAC estimate.
  • Be honest about the number of drinks and their alcohol content for a more realistic estimate.
  • Remember that individual metabolism varies; the calculator provides an average estimate.
  • Always plan a safe ride home if you have consumed any alcohol.

Common Mistakes to Avoid

  • Underestimating the number of drinks consumed, which leads to a lower BAC estimate.
  • Assuming the calculator is a legal or medical tool; it is only an estimate.
  • Ignoring that time elapsed since drinking affects BAC; entering the correct time is crucial.

Last updated: August 13, 2026