Last updated: September 12, 2026
Search EtG detection time chart and you usually get a table pretending every body clears on the same Tuesday. Urinary ethyl glucuronide does not work that way. Hours-to-clear depend on how much ethanol you absorbed, which cutoff the program printed, and a decay curve that is faster at first, then slower.
This page is the visual companion to the ETG Detection Time Calculator. The bars below are the same biphasic teaching model (about 3.5-hour fast phase, then a slower tail). Pair it with the EtG Alcohol Calculator for a level-at-time-X view, or the ETG Half-Life Calculator if you already have a lab ng/mL.
How to read the chart
X-axis: NIAAA standard drinks in one sitting (1, 2, 4, 6, 8). Y-axis: estimated hours until the modeled concentration falls under each cutoff. Three bars per drink count: 100, 300, and 500 ng/mL.
Fixed sketch for the picture: 170 lb male, two hours of drinking, then abstinence. Change sex, weight, or duration on the calculator — do not eyeball a bar and call it your result.
If a bar is only a couple of hours high, that cutoff was already close to the peak. If 100 ng/mL is still a tall bar after eight drinks, the sensitive line is still using the slow tail.
100 vs 300 vs 500 ng/mL
| Cutoff | How CalcGrain uses it | Chart meaning |
|---|---|---|
| 100 ng/mL | Strict / zero-tolerance monitoring | Longest bar in every group |
| 300 ng/mL | Standard clinical / workplace middle | Middle bar |
| 500 ng/mL | Less sensitive general screen | Shortest bar; more buffer vs incidental ethanol in published exposure work |
There is no single SAMHSA-mandated EtG cutoff for every clinic. SAMHSA’s advisory language is that EtG/EtS at low levels cannot reliably separate drinking from other ethanol exposure, and that life-altering decisions should not rest on EtG alone.
Modeled hours by drink count
Estimated hours to clear (CalcGrain biphasic model · 170 lb male · 2-hour session)
| Standard drinks | Hours to 100 ng/mL | Hours to 300 ng/mL | Hours to 500 ng/mL |
|---|---|---|---|
| 1 | 13.3 | 4.5 | 1.9 |
| 2 | 28.7 | 14.4 | 7.9 |
| 4 | 40.0 | 25.8 | 19.1 |
| 6 | 46.0 | 31.7 | 25.1 |
| 8 | 50.0 | 35.8 | 29.2 |
These hours are copied from the same functions the live calculator uses (estimatePeakETG and hoursToClearCutoffBiphasic). They will drift if you change body weight or drinking duration.
Worked example: two drinks vs six
Two standard drinks in this sketch: 100 ng/mL still modeled positive into the second day (~29 hours); 500 ng/mL already under in about 8 hours. Six drinks: 100 ng/mL ~46 hours; 300 ng/mL ~32 hours; 500 ng/mL ~25 hours.
That is why “will I pass in 48 hours?” is a cutoff question. At 500 ng/mL after two drinks, 48 hours is usually empty in the model. At 100 ng/mL after six drinks, 48 hours is close to the line, not a slogan. For the 48-hour framing, see Pass EtG test in 48 hours?.
What the model does not know
New drinks after the sitting, heavy hydration that flags creatinine, liver or kidney disease, and incidental ethanol (mouthwash, sanitizer) are outside this chart. Stacked nights belong on the Advanced ETG Calculator. Product-by-product incidental exposure belongs on the false-positive deep dive.
Hair and PEth are different families — compare them in how long alcohol stays in your system.
Who this chart is for
Use it when a program named urine EtG and a cutoff, and you want to see why 100 ng/mL lasts visibly longer than 500 ng/mL on the same sitting. Do not use it for a breathalyzer, a hospital ethanol draw, PEth, or hair. Do not use it to plan drinking around a test.
The 170 lb male sketch is a teaching row, not a population average for women, heavier or lighter bodies, or multi-day use. Sex and weight change peak EtG in the same Widmark-style first step the live calculator uses. A 130 lb female with four drinks will not match the four-drink bars on this page.
If you already have a lab ng/mL, skip the drink-count chart and use the ETG Half-Life Calculator so the starting concentration is the number on the report rather than a modeled peak.
Readers comparing this chart with Omnicalculator-style pages should look for three things: named cutoffs (100 / 300 / 500 ng/mL), a stated body-weight sketch, and an honest “modeled, not a chromatogram” line. A prettier PNG of invented hours is worse than a CSS bar that matches the live calculator.
Why the bars are estimates
The site’s biphasic curve is a teaching fit: a faster early drop, then a slower tail. Real urinary EtG is also diluted by how much water is in the bladder, when you last voided, and whether creatinine will flag the cup. A “19 hours to 500 ng/mL” bar after four drinks assumes the modeled peak was real and then decayed with no new ethanol.
Literature half-lives for EtG are often quoted in a roughly 2–5 hour band for the faster phase. CalcGrain pins 3.5 hours fast / 9 hours slow so every EtG tool on the site tells the same story. That consistency matters more for trust than inventing a new constant per article.
Creatinine and specific gravity sit outside the bar chart on purpose. A dilute cup can lower every dissolved marker and still fail a validity rule even when the EtG number looks “better.” Over-hydrating to chase a shorter bar is how people earn a re-collect. The hours in the table assume a valid specimen after a single sitting.
If you need the same hours with your weight and sex, ignore the PNG-style intuition and type the drinks into the detection time calculator. This page exists so the 100 / 300 / 500 ng/mL grouping is visible in one view — the query “etg detection time chart” and “realistic etg detection times” both want that picture, labeled as a model, with drink count on the x-axis and hours on the y-axis.
Frequently Asked Questions
What is an EtG detection time chart?
It plots estimated hours until urinary EtG falls below common cutoffs (100, 300, and 500 ng/mL) against how many standard drinks you entered. CalcGrain’s chart uses the same biphasic teaching model as the ETG Detection Time Calculator — not a lab chromatogram.
How long does EtG stay detectable after 4 drinks?
For a 170 lb male, two-hour session, the model estimates about 40 hours to clear 100 ng/mL, 26 hours for 300 ng/mL, and 19 hours for 500 ng/mL. Weight, sex, extra sessions, and hydration change that. Run your own inputs on the calculator.
Why do 100, 300, and 500 ng/mL charts look so different?
Lower cutoffs stay “positive” longer because the decay curve has to fall farther. 100 ng/mL is the strict/zero-tolerance monitoring line; 300 ng/mL is a common clinical/workplace middle; 500 ng/mL is a less sensitive screen.
Is this chart a lab guarantee?
No. It is a modeled estimate using a 3.5-hour fast phase and a slower tail. Individual metabolism, new drinks, and specimen validity can disagree with the picture. Only the laboratory result counts.
Do more drinks always add the same extra hours?
No. The relationship is not a straight line. Going from one drink to two adds more hours at 100 ng/mL than going from six drinks to eight in this model, because decay is logarithmic in each phase.
Can I use this chart for PEth or hair?
No. PEth is a blood marker over weeks (20/50/200 ng/mL on this site). Hair EtG is pg/mg over months. This chart is urine EtG only.
What is a standard drink on the x-axis?
NIAAA: 14 grams of ethanol — 12 oz beer at 5%, 5 oz wine at 12%, or 1.5 oz spirits at 40%. Craft pours often count as more than one.
Where should I model stacked nights?
Use the Advanced ETG Calculator. This chart assumes one session, then time passing with no more ethanol.
Sources
- NIAAA — What is a standard drink?
- SAMHSA advisory language on EtG/EtS as exposure markers, not standalone life-altering proof
- CalcGrain EtG model constants — 100 / 300 / 500 ng/mL cutoffs; biphasic 3.5 h / 9 h teaching curve on the detection time tool
Open the ETG Detection Time Calculator and enter your drinks rather than memorizing a bar height.