Project a concentration forward
Use a real quantitative lab result if you have one, or a hypothetical number to explore the math. This tool does not estimate a starting concentration from drink count.
| Hours | Remaining range (ng/mL) |
|---|---|
| 0h | 4.0k–4.0k |
| 3h | 1.4k–2.0k |
| 6h | 500–1.0k |
| 9h | 177–500 |
| 12h | 63–250 |
| 18h | 8–63 |
| 24h | 1–16 |
| 36h | 0–1 |
| 48h | 0–0 |
| 72h | 0–0 |
This is a model of the decay math applied to the number you entered—not a prediction of your actual result. See the calculation formula guide for why a starting concentration can't be derived from drink count.
Important: this tool applies decay math to whatever number you enter. It does not estimate a starting concentration from drink count, and it cannot predict an actual laboratory result.
What “half-life” means here
Half-life is the time it takes a concentration to fall by half. Published research on urinary EtG generally reports an elimination half-life of roughly 2 to 3 hours, which is why this tool shows every projection as a range between those two bounds rather than picking one number and presenting it as exact.
Why this tool doesn't start from your drink count
Half-life describes the shape of a decline once you have a starting point. It says nothing about what that starting point is. Peak EtG concentration after drinking depends on dose, absorption speed, food, body composition, sex, hydration, and individual metabolism—factors that can shift a real peak several-fold between two people who drank the same amount. Picking one fixed “ng/mL per drink” number and running it through this formula would only dress up a guess as a precise result. Read the calculation formula guide for the full explanation.
How to get a useful starting number
- Use the actual value from a quantitative laboratory report if you have one.
- Use a hypothetical number to understand how the math behaves, not to predict a real test outcome.
- For an estimate built from drinks and elapsed time instead of a known concentration, use the EtG urine calculator or the EtG timeline calculator.
What this calculator cannot know
- Your actual peak EtG concentration
- Your individual elimination rate
- Urine creatinine or sample dilution at collection
- The laboratory's method, confirmation policy, or reporting cutoff
For the broader research context, see the EtG detection-window guide and the quantitative EtG levels research summary.