Blood Alcohol Elimination Calculator 2026
Estimate your blood alcohol content and roughly how long your body needs to eliminate it, based on the widely used Widmark formula. For education and planning ahead only — never a substitute for waiting it out and never a green light to drive.
Estimate BAC, Track a Drinking Session
Get a rough estimate of current BAC and elimination time, or log several drinks over an evening to see how your estimated level changes hour by hour. Both are estimates for education, not a measurement of your actual impairment.
Quick BAC Estimate
Rough estimate of current BAC and time until it reaches zero
1 standard drink ≈ 14g alcohol (12oz beer, 5oz wine, 1.5oz spirits)
Reflects average body water % differences used in Widmark’s formula
BAC Estimate Result
Estimated current level and rough time to zero
Enter drinks, time elapsed, and your details, then click Estimate BAC.
Drinking Session Tracker
Log drinks spread across an evening for a fuller picture
Time from first drink to last drink
Affects the shape of the estimated BAC curve, not just the peak
Session Estimate Result
Estimated peak, hourly curve, and time to zero
Enter your session details, then click Build Session Estimate.
BAC Effects & Legal Limits Quick Reference
Typical effects associated with rising BAC levels, and common legal limits for driving. Individual impairment varies widely and can occur below these levels — always check the specific law for your location.
| BAC Level | Typical Effects | Notes |
|---|---|---|
| 0.02% | Mild relaxation, slight mood change | Some judgment effects begin |
| 0.05% | Reduced coordination, lowered alertness | Scotland & much of Europe’s driving limit |
| 0.08% | Impaired coordination & reasoning | Common US & UK driving limit |
| 0.10% | Clearly slurred speech, slower reaction | Significant impairment |
| 0.15% | Major balance & coordination loss | High-risk range |
| 0.20%+ | Confusion, possible blackout risk | Medical risk increases sharply |
| 0.30%+ | Severe impairment, loss of consciousness risk | Seek medical attention if reached |
| 0.40%+ | Risk of coma or death | Medical emergency — call for help |
Blood Alcohol Elimination FAQ
Everything people ask about how alcohol is processed and eliminated by the body.
The liver metabolizes alcohol at a fairly constant rate, roughly 0.015-0.017 BAC per hour for most adults, regardless of how much was consumed. This is a linear elimination process, not exponential, which is why drinking coffee, taking a cold shower, or exercising does not speed it up.
The most common method is the Widmark formula, which factors in grams of alcohol consumed, body weight, a sex-based body water distribution constant, and time elapsed since drinking began. It produces a rough estimate, not a precise measurement — actual BAC varies with metabolism, food intake, medication, and other individual factors.
On average, it takes about 1 to 1.5 hours for the body to metabolize the alcohol in one standard drink, though this varies by individual. A standard drink is typically defined as 14g of pure alcohol — about a 12oz beer, 5oz glass of wine, or 1.5oz shot of spirits.
No. BAC calculators give a rough estimate only and can be significantly off due to individual differences in metabolism, food intake, medications, hydration, and health conditions. Impairment can occur well below the legal limit, and the only guaranteed way to avoid driving impaired is to not drive after drinking at all.
In most of the United States, the legal limit for drivers over 21 is 0.08% BAC, with lower limits (often 0.02-0.04%) for commercial and underage drivers. Many countries, including most of the UK (0.08%), Scotland (0.05%), and much of Europe (0.05%), set their own limits, so local law should always be checked directly.
No. Food slows the absorption of alcohol into the bloodstream, which can lower peak BAC, but it does not speed up the rate at which the liver eliminates alcohol already absorbed. Water, coffee, and exercise have no meaningful effect on elimination rate either — only time reduces BAC.