BAC Calculator
Estimate your blood alcohol content (BAC) with the Widmark formula from your weight, sex, standard drinks and time. For education only — never use it to decide whether to drive.
| BAC threshold | Time remaining to reach | Notes |
|---|
| Country | Legal limit | Notes |
|---|---|---|
| United States | 0.08% | Federal guideline; Utah 0.05%. Commercial drivers often 0.04%. |
| United Kingdom | 0.08% | England, Wales, Northern Ireland. Scotland: 0.05%. |
| Australia | 0.05% | Learner/provisional drivers: 0.00% in most states. |
Metabolism baseline? BMR calculator · sober-up timer: Countdown timer · sleep recovery: Sleep calculator.
About this BAC estimate
The Widmark formula gives a rough blood alcohol estimate from your weight, sex, number of standard drinks and time elapsed. Real BAC depends on food, metabolism, medication and more. This tool is for education only — it cannot tell you whether you are safe to drive.
FAQ
What can I use BAC Calculator for?
BAC Calculator is useful when you need to estimate your blood alcohol content (BAC) with the Widmark formula from your weight, sex, standard drinks and time. For education only — never use it to decide whether to drive. It is meant for quick checks, everyday workflows and practical tasks where a fast browser-based result is enough.
How do I use BAC Calculator correctly?
Enter accurate body, time, activity or goal values. The estimate is only as good as the measurements you provide.
What input does BAC Calculator need?
Use the fields shown in the tool and keep the input close to the real case you want to solve. If the page includes examples or presets, start with those to understand the expected format.
What result does BAC Calculator give me?
The tool returns health-related estimates, categories or target ranges based on the inputs shown on the page. In most cases the output updates instantly and can be copied, downloaded or used as a reference for your next step.
How accurate is BAC Calculator?
Use the result as a practical reference, not as medical advice. Personal health decisions should be checked with a qualified professional.
Is my data uploaded when I use BAC Calculator?
The tool is designed to run in your browser, so ordinary inputs are processed locally unless a page explicitly states that it needs an online lookup.
What common mistakes should I avoid with BAC Calculator?
Avoid guessing measurements, mixing metric and imperial units, or treating an estimate as a diagnosis.
What related tasks can BAC Calculator help with?
BAC Calculator is intended for use cases related to "bac calculator" and nearby needs such as "blood alcohol calculator". For best results, follow the labels, examples and options on the page.
What are the limits of BAC Calculator?
It is a planning tool, not a professional advisor. Local rules, personal circumstances and real-world conditions can change the final answer.
When should I double-check the output from BAC Calculator?
Double-check the output before changing health, diet, training or medication decisions.