Health tool
ETG CalculatorEstimate Alcohol Detection Window
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Widmark formula
Estimate how long Ethyl Glucuronide (ETG) -- an alcohol metabolite -- may be detectable in a urine test after drinking. Enter your body weight, biological sex, and the number of drinks to get a rough ETG detection window estimate.
Disclaimer: Estimates only. Not for legal, medical, or safety decisions.
Your Details
Based on your inputs, ETG may be detectable in urine for up to 36 hours. Your estimated peak BAC is 0.085% -- you would reach a zero BAC in approximately 5.7 hours. These are rough estimates, not medical fact.
ETG Detectable Up To
36 hrs
Estimated urine window
0.085%
Peak BAC (est.)
5.7 hrs
Time to Sober
Important Disclaimer
Results are estimates only. Do not use this tool to make decisions about compliance, driving, employment, court requirements, or medical treatment.
Getting started
How to Use the ETG Calculator
This tool quickly estimates how long alcohol metabolites might remain in your system.
1
Enter your physiology
Select biological sex (determines Widmark r-factor) and enter body weight.
2
Enter consumption details
Input the number of standard drinks and average ABV percentage.
3
Review the estimates
ETG detection window, peak BAC, and time to sober appear instantly.
The calculation
Step-by-step: how these estimates are calculated
Here is exactly how the estimation works based on the Widmark formula.
1
Step 1: Calculate total alcohol consumed
Each standard US drink contains approx. 14 g of pure ethanol.
Alcohol = drinks x 14 g
= 3 x 14
= 42.0 g of ethanol
2
Step 2: Estimate peak BAC (Widmark formula)
BAC = (alcohol in grams / (body weight kg x r-factor x 1000)) x 100
r-factor = 0.68 (male body water ratio)
= (42.0 / (72.6 x 0.68 x 1000)) x 100
= (42.0 / 49351) x 100
= 0.085% BAC (estimated peak)
3
Step 3: Estimate time to reach zero BAC
Average alcohol metabolism rate: 0.015% BAC per hour
Hours to sober = peak BAC / 0.015
= 0.085 / 0.015
= approx. 5.7 hours
4
Step 4: Estimate ETG detection window
Base window: 24 hrs (light session)
Add 4 hours per drink to account for higher ETG load
= base + (3 x 4) capped at 80 hrs max
= up to 36 hours (estimated)
Reference
ETG Detection Window by Cutoff Level
The detection window depends on both how much was consumed and which cutoff threshold is used by the testing program:
| Amount consumed | 100 ng/mL cutoff | 250 ng/mL cutoff | 500 ng/mL cutoff |
|---|---|---|---|
| 1--2 standard drinks | Up to ~36 hrs | Up to ~24 hrs | Up to ~12 hrs |
| 3--5 standard drinks | Up to ~60 hrs | Up to ~48 hrs | Up to ~36 hrs |
| 6+ standard drinks | Up to ~80 hrs | Up to ~72 hrs | Up to ~60 hrs |
General estimates based on published ETG research. Actual detection times vary by individual and testing conditions.
Strategy
Quick Tips for Understanding Your ETG Estimate
Cutoff level matters most
The cutoff level (100 / 250 / 500 ng/mL) matters more than the total hours -- always confirm which threshold your program uses.
No proven way to speed clearance
Hydration helps metabolic processes generally, but deliberately diluting urine is flagged by modern tests.
BAC vs ETG
A reading of zero BAC does NOT mean zero ETG. A person can be completely sober (0.00% BAC) and still test positive days later.
Examples
Typical ETG scenarios
See how the amount consumed changes the detection window estimates.
Light
2 beers (5% ABV)
100 ng/mL Cutoff
24-36 hrs
Detection window
Moderate
4 glasses of wine (12% ABV)
100 ng/mL Cutoff
48-60 hrs
Detection window
Heavy
8 shots of liquor (40% ABV)
100 ng/mL Cutoff
72-80 hrs
Detection window
FAQ
Frequently asked questions
Q
What is ETG?ETG (Ethyl Glucuronide) is a direct metabolite of ethanol produced when the liver processes alcohol. Unlike BAC tests that measure alcohol itself, ETG urine tests detect evidence that alcohol was consumed - even after the alcohol has been fully eliminated from the body. ETG can remain detectable in urine long after a person feels completely sober.
Q
How long is ETG detectable in urine?ETG is generally detectable in urine for up to 80 hours after drinking, depending on the amount consumed and individual metabolism. Light drinking (1-2 drinks) may produce detectable ETG for 24-36 hours. Heavier consumption (6+ drinks) can extend detection to 60-80 hours. These are estimates - actual detection times vary significantly.
Q
What is the ETG cutoff level for urine tests?Common cutoff thresholds for ETG urine tests are 100 ng/mL (highly sensitive), 250 ng/mL (moderate sensitivity), and 500 ng/mL (standard sensitivity). Tests at 100 ng/mL may detect even incidental alcohol exposure. The cutoff used by a specific testing program affects whether a result is reported as positive or negative.
Q
What is the difference between ETG and BAC?BAC (Blood Alcohol Concentration) measures the amount of alcohol currently present in the bloodstream. It drops to zero hours after drinking stops. ETG measures a metabolic byproduct of alcohol that persists in urine for days. A zero BAC does not mean a zero ETG - the two tests measure very different things.
Q
Does the number of drinks affect how long ETG is detectable?Yes. More alcohol consumption produces more ETG. Heavier drinking sessions generate higher ETG concentrations that take longer to drop below the test's detection threshold. The relationship is not perfectly linear - individual metabolism, hydration, and liver function all play a role.
Q
Is this ETG calculator medically accurate?No. This tool provides rough estimates based on the Widmark formula for peak BAC and general ETG research guidelines. Many variables - food intake, hydration, liver function, kidney function, body composition, and medication - affect actual ETG metabolism and detection. Never use this tool to make legal, medical, employment, or safety decisions.
Q
What counts as one standard drink?In the US, one standard drink contains approximately 14 grams of pure ethanol. This is equivalent to: 12 oz regular beer at 5% ABV, 5 oz wine at 12% ABV, or 1.5 oz distilled spirits at 40% ABV. Drinks served at bars or at home are often larger than one standard drink.
Q
Is this ETG calculator free?Yes - completely free with no sign-up required. All calculations run in your browser.
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