About ToolSite
EtG Calculator is a free, research-based tool that estimates how long Ethyl Glucuronide (EtG) remains detectable in urine after alcohol consumption. We built it because the standard information available online — “EtG stays in your system for up to 80 hours” — is both technically accurate and practically useless. The actual window depends on how much you drank, your body weight, your test's cutoff level, and several other variables. Generic ranges don't help people understand their specific situation.
The Research Behind the Tool
Our calculator uses a pharmacokinetic model grounded in peer-reviewed clinical research. The primary sources are Høiseth G. et al. (Forensic Science International, 2007), which documented peak urine EtG concentrations following controlled alcohol administration in human subjects, and Wurst FM. et al. (Addiction, 2003), which established the foundational EtG elimination kinetics data most subsequent research builds on.
From these studies, we derived the core model parameters: peak EtG concentration of approximately 400 ng/mL per standard drink at a 70 kg reference body weight, an EtG urine half-life of 3.0 hours (midpoint of the published 2.5–3.5 hour range), and a first-order elimination model that calculates the detection window from peak to threshold. SAMHSA's mandatory guidelines for federal workplace drug testing inform the cutoff level definitions. Hydration adjustments are derived from Wurst et al.'s documentation of fluid-intake effects on EtG urine concentration.
What This Tool Is and Isn't
The estimates this tool produces are statistical averages from a population-based model. Your individual metabolism — specifically your UDP-glucuronosyltransferase enzyme activity, kidney function, and liver health — affects your actual EtG elimination rate in ways the model can't fully capture. Published data shows 20–40% inter-individual variation in EtG excretion even among people with similar body weights, drink counts, and hydration levels.
This tool is designed for educational and informational purposes. It helps people understand the pharmacokinetics of EtG testing — how the test works, what drives detection windows, why the cutoff level matters so much, and what the research actually says versus generic online claims. It should not be used to plan around legitimate sobriety monitoring requirements or to circumvent compliance obligations.
Our Editorial Process
Content on EtG Calculator is written by our editorial team with reference to the primary scientific literature. Each tool specification and blog article cites the specific studies it draws from. We review the underlying data periodically and update content when new research is published or when we identify areas where the model can better reflect the literature. The Last Updated date on each page reflects when we last reviewed and verified the content.
We don't fabricate ratings, invent expert credentials, or use speculative data. Every number in the calculator's outputs traces back to a published source listed in the methodology section.
Who Uses This Tool
People in alcohol monitoring programs — probation, drug courts, DUI diversion, treatment compliance — use this tool to understand what EtG detection windows actually look like for specific drinking scenarios. Healthcare providers and counselors in addiction medicine use it to explain EtG pharmacokinetics to patients in concrete rather than abstract terms. Students and researchers in toxicology and forensic science reference it as a quick calculation check against published data.
Contact Us
Found an error in our calculations? Have a question about the methodology? Want to suggest a topic for our blog? Reach us at contact@example.com. We review all messages and respond to substantive questions about the research and methodology.