2 drinks, 5% ABV
- Alcohol consumed
- 28.0095 g
- Estimated time to zero
- 2.4325367647 hours
- Widmark estimate
- male
Never use this estimate to decide whether it is safe or legal to drive.
BAC Calculator
Use this free BAC calculator for an educational blood alcohol concentration estimate from drinks, ABV, body weight, sex, and time.
Estimate, not diagnosisFormula notesExample inputsTab-only history
Formula steps
- Estimate grams of alcohol from drink volume, ABV, and drink count.
- Apply a Widmark-style body-water factor by sex and body weight.
- Subtract an average elimination rate for elapsed time.
Examples
Recent answers
Recent BAC estimates will appear here.
BAC estimates are not legal, medical, or driving advice. Do not use them to decide whether to drive.
Inputs and recent answers stay in this browser tab and are not sent to a server.
How to use the BAC Calculator
- Enter the requested measurements, dates, lab values, or workout details.
- Check that the units and formula assumptions match what the tool is asking for.
- Press the calculate button to see the answer, supporting metrics, and formula steps.
- Read the estimate with the health disclaimer in mind, then copy the result if you need it for notes.
What people use it for
Understand how drink count, ABV, body weight, and time affect an estimate.
Compare different drink sizes and strengths.
See why BAC estimates are uncertain.
Avoid using estimates for legal or safety decisions.
Quick examples
Two beers
Male, 80 kg, 2 x 355 mL at 5%, 1 hourAbout 0.0365% BAC; estimated 2.43 hours to zero
Wine example
Female, 65 kg, 2 x 150 mL at 12%, 2 hoursAbout 0.0495% BAC; estimated 3.3 hours to zero
Spirit drink
Male, 90 kg, 1 x 45 mL at 40%, 1 hourAbout 0.0082% BAC; estimated 0.55 hours to zero
Need the guide or a nearby tool?
Need a slower walkthrough, a related calculator, or the full library? These links keep you close to the task you started.
- How to use the BAC CalculatorSee slower examples, input meanings, formula notes, result limits, and mistakes to avoid.
- Health & FitnessBrowse related calculators and utilities in the same category.
- Calculator and utility guidesFind more guides that use real tool inputs and example numbers.
- All free toolsSearch every live tool, converter, calculator, AI helper, and browser utility.
Frequently asked questions
Plain-language answers about when to use the estimate, what the formula means, what it cannot decide for you, and how privacy works.
When should I use the BAC Calculator?
Use it for simple educational checks, trend tracking, or planning tasks like these: Understand how drink count, ABV, body weight, and time affect an estimate. Compare different drink sizes and strengths. It can help you understand a number, but it cannot explain your whole health situation.
What do the main BAC Calculator inputs mean?
Enter the formula sex setting, body weight in kilograms, number of drinks, drink size in milliliters, ABV percent, and hours since the first drink. Use the actual pour size and alcohol percentage when you know them. A strong mixed drink or large pour can count as more alcohol than one ordinary serving.
What is the BAC Calculator doing with my inputs?
In plain language: The calculator estimates grams of alcohol from drink volume, ABV, drink count, and 0.789 g/mL ethanol density, applies a Widmark-style body-water factor, then subtracts 0.015 percentage points per hour as a rough elimination estimate. Read the result together with the notes on the page, because health and fitness numbers often need personal context.
How should I read the BAC Calculator result?
Read BAC as a rough educational estimate for the inputs you typed, not as a legal, medical, workplace, or driving decision. Real BAC can differ because food, drinking speed, medications, tolerance, health, body composition, and test timing all matter.
Can I use this BAC estimate to decide whether to drive?
No. Do not use this calculator to decide whether it is safe or legal to drive. Laws, enforcement tests, body differences, medication, food, timing, and impairment can all matter, so the safest practical answer is not to drive after drinking.
What does Widmark-style mean on this page?
It means the calculator estimates grams of alcohol, divides by body weight and a broad body-water factor, then subtracts an average elimination amount for elapsed time. It is a learning estimate, not a breathalyzer, blood test, or legal standard.
Why do drink size and ABV matter so much?
The alcohol grams come directly from volume and ABV. A large craft beer, heavy wine pour, or strong mixed drink can contain much more alcohol than a small standard serving, so entering the label and pour size matters more than the drink name.
Can I use this as medical advice?
No. This estimate is not legal, medical, or driving advice. Do not use it to decide whether to drive or perform safety-sensitive tasks. Use the calculator as a learning tool, then ask a qualified professional about decisions that affect care, pregnancy, medication, nutrition, or safety.
What should I double-check before trusting the result?
Check the units, date, and personal details before reading the answer. For example, pounds and kilograms, inches and centimeters, or a wrong activity level can change the result quickly. If the number feels surprising, rerun it slowly and compare it with the examples.
Does the site save my health inputs?
No. The calculator runs in your browser tab. Recent answers stay only on the page while you use it, and they are not sent to a server.