𧫠EtG Detection Time Estimator
Rough detection windows for the urine alcohol metabolite test.
For informational purposes only, not medical advice. Consult a healthcare professional.
EtG (ethyl glucuronide) can be detected in urine up to about 80 hours after heavy drinking at the standard 500 ng/mL cutoff, and roughly 24 to 48 hours after light drinking. This estimator gives the typical window for your drink count and cutoff, but individual variation is large: treat it as a range, never a promise.
How to Use This Estimator
EtG is a direct metabolite of ethanol, detectable long after blood alcohol hits zero. Courts, employers, and treatment programs use it because the window stretches days, not hours.
Enter standard drinks (14 g pure alcohol each: 12 oz of 5% beer, 5 oz of 12% wine, 1.5 oz of 80-proof spirits). Count honestly; undercounting is the main error.
Enter hours since your last drink and select the test cutoff. 500 ng/mL is the common standard; 100 ng/mL is the sensitive version with a longer window.
Read the typical window and the assessment. "Likely below cutoff" means typical, not certain: hydration, metabolism, and test specifics shift real results.
Typical Detection Windows
EtG forms when the liver conjugates a small fraction of ethanol with glucuronic acid, and it clears in urine far slower than ethanol itself. Peak urine EtG occurs roughly 8-12 hours after drinking ends, then declines with a half-life near 2-3 hours in most studies, though the tail stretches. The 80-hour figure comes from heavy-drinking studies at 500 ng/mL; light drinking often clears by 24-36 hours. Higher cutoffs shorten windows and cut incidental-exposure positives, which is why SAMHSA's advisory discusses 500 ng/mL as the standard for legal/forensic use while clinical programs sometimes use 100.
Worked Example
Four standard drinks ending at midnight, test at midnight the next night (24 hours later), 500 ng/mL cutoff: typical window for 3-4 drinks is about 48 hours, so at 24 hours the result would likely still be positive. Same scenario at 72 hours: past the typical 48-hour window, likely negative, but heavy individuals and slow metabolizers can exceed typical ranges. One glass of wine (1-2 drinks) with 48 hours elapsed at 500 ng/mL: at the edge of the typical 24-48 hour window, genuinely uncertain. The calculator's windows mirror these published ranges; your body gets the final vote.
What Changes Your Window
| Factor | Effect on detection |
|---|---|
| Amount and pace | More drinks, longer window; the dominant factor |
| Hydration | Dilute urine can dip below cutoff; labs check creatinine to catch dilution |
| Body composition | Higher body water dilutes; varies the peak |
| Liver function | Impaired metabolism can extend the tail |
| Cutoff level | 100 ng/mL adds roughly 12-24 hours vs 500 |
| Incidental exposure | Mouthwash, sanitizer can trigger 100 ng/mL, rarely 500 |
Incidental exposure deserves emphasis: alcohol-based mouthwash and hand sanitizer have produced positives at 100 ng/mL in studies, which is exactly why forensic programs prefer 500. If you are in a testing program, disclose every exposure source and ask which cutoff they use; the answer changes what "positive" means. Dilution games usually fail: labs measure creatinine and specific gravity, and dilute samples get flagged or rejected. For alcohol's other math, our BAC calculator estimates blood alcohol from drinks and time, and our nicotine dependence test covers the other common substance screen.
What This Estimator Cannot Do
It cannot tell you that you will pass a test. Published windows are ranges from studies, and you do not know where in the range you fall. EtG tests also vary: immunoassay screens with LC-MS confirmation, different labs, different hydrolysis steps. If abstinence is required of you (court, custody, employment, recovery program), the only safe strategy is abstinence with margin, not arithmetic. This page is informational; it is not advice for beating a test, and attempting to adulterate a sample is a separate offense in many programs.
If Drinking Is the Concern
A test-date countdown is sometimes a sign worth listening to. If you are calculating detection windows because drinking is colliding with work, family, or the law, that collision is itself information. SAMHSA's National Helpline (1-800-662-4357) is free, confidential, and 24/7, and brief counseling works for many people long before dependence develops. The AUDIT alcohol screen (ask your clinician) takes two minutes and tells you where you stand.
EtG vs Breath and Blood Testing
Each alcohol test answers a different question. Breath and blood measure current intoxication over hours; EtG measures recent consumption over days. A breathalyzer at zero with a positive EtG is not a contradiction: it means sober now, drinking within the window. Employers use breath for reasonable-suspicion testing and EtG for abstinence monitoring. Hair testing stretches the window to months. Understanding which question is being asked prevents the common confusion of "but I blew zero" after a positive EtG; both results can be correct simultaneously.
For informational purposes only, not medical advice. Consult a healthcare professional.
Frequently Asked Questions
How long does EtG stay in urine?
Up to ~80 hours after heavy drinking at the 500 ng/mL cutoff; 24-48 hours after light drinking. The sensitive 100 ng/mL cutoff extends windows by roughly 12-24 hours. Individual variation is wide.
What is EtG?
Ethyl glucuronide, a direct metabolite formed when the liver conjugates ethanol with glucuronic acid. Unlike ethanol itself, it lingers in urine for days, making it useful for abstinence monitoring.
Can mouthwash cause a positive EtG?
At the 100 ng/mL cutoff, yes in studies; alcohol-based mouthwash and hand sanitizer have produced positives. At 500 ng/mL it is rare. This is why forensic programs prefer the higher cutoff.
Does drinking water help pass an EtG test?
Dilution can lower concentration below cutoff, but labs test creatinine and specific gravity to detect dilute samples, which are typically flagged or rejected. It is not a reliable strategy.
What is the difference between EtG and EtS?
EtS (ethyl sulfate) is the other direct ethanol metabolite, usually tested alongside EtG. The pair improves accuracy; EtS is less affected by bacterial urine contamination that can rarely degrade EtG.
Can EtG be detected in hair?
Yes, hair EtG testing covers months rather than days and is used in some legal and workplace contexts. It requires sufficient hair length and has its own cutoff controversies.
Does EtG detect one beer?
Possibly at 100 ng/mL within the first day; at 500 ng/mL a single drink often falls below cutoff after ~24 hours. Light-drinking studies show wide individual variation around these lines.
What cutoff do courts use for EtG?
Commonly 500 ng/mL per SAMHSA advisory guidance for legal/forensic use, balancing detection against incidental-exposure false positives. Programs vary; ask which cutoff applies to you.
Can diabetes cause false positive EtG?
Urinary tract infections with certain bacteria can theoretically produce EtG from urinary glucose in diabetics, and EtS testing guards against this. Confirmed false positives are rare with proper lab confirmation.
How accurate are EtG tests?
Screening immunoassays are good but imperfect; positives are typically confirmed by LC-MS/MS, which is highly specific. The main accuracy debates concern cutoffs and incidental exposure, not the chemistry.