Nomicho

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How "how drunk am I right now?" gets predicted in real time

Mid-drink, have you ever wondered exactly how drunk you are? You can sort of feel it — a flush, a lift in mood — but you can't see it as a number. Nomicho is an iPhone app that, just from logging what you drank, shows your estimated blood alcohol concentration and an intoxication stage on the spot. Here's how that prediction actually works.

Log a drink, and it computes your curve

Every drink you log recomputes your blood alcohol concentration over time — not a back-of-the-envelope guess, but established alcohol pharmacokinetics: how alcohol entering the body is absorbed, distributes, and clears. Roughly 25% is absorbed in the stomach and most of the rest in the small intestine, with nearly all of it entering the blood,[1] then broken down in the liver at a speed that varies from person to person.[1][6]

The same amount hits people differently

Two people can drink the same canned highball and end up in different places. Nomicho accounts for sex, weight, height, and flush response, so it reflects that.[4][5] In Japan especially, many people flush easily (weaker ALDH2) — which bears less on the concentration itself than on how rough a given concentration feels. Flushing comes from how you process acetaldehyde, a by-product of breaking alcohol down, not from the alcohol itself — so two people at the same concentration can feel very different. That's why Nomicho asks about flush response up front.

Reading it as a "stage"

Blood alcohol concentration determines the degree of intoxication.[2] It's commonly described in stages — pleasant, tipsy, inebriated, and so on.[3] Nomicho shows your computed concentration as one of these stages, so you can read it as a state, not just a number.

Pleasant 0.02–0.04%
Tipsy 0.05–0.10%
Excited 0.11–0.15%
Confused 0.16–0.30%
Stupor 0.31–0.40%
Coma 0.41%〜
Blood alcohol concentration and the stages of intoxication (general guide)

Rising or falling right now?

Concentration doesn't peak the instant you finish a drink. Alcohol takes time to absorb from the stomach and small intestine into the blood, so even after your last drink your level keeps climbing for a while. The peak lands a little after you stop — sooner on an empty stomach, more gradually if you've eaten.[7] "I've stopped, so I'm fine" can be true while your concentration is in fact still rising.

So Nomicho shows not just the current number but the direction — whether your level is still climbing or has begun to fall — along with where it's headed next, and your pace.

A range, not a single value

This is the big difference from a typical calculator. Because body chemistry and condition carry real uncertainty, Nomicho shows the concentration not as one value but as an estimated range, with the error leaned toward caution (higher, slower to clear). As below: the same "now," seen as a range rather than a point.

beer 1 beer 2 Nomicho: a range most apps: one value 0306090120180 minutes since first drink concentration (higher ↑) band = estimated range
Two medium beers, 30 min apart — how t = 60 min looks (illustrative)

Why it can't be pinned to a single number is covered in detail in "How long until alcohol wears off? Why there is no single number."

What it can't do

Nomicho's prediction is not a measuring device. It doesn't sense your actual level the way a breathalyzer does — it's an estimate from your inputs and a general model. So never use it to decide whether you can drive, or for any legal or medical judgment.

From logging to prediction

The bar and restaurant staples are built in, so logging a drink is one tap — down to mug and can sizes — with pure alcohol grams computed automatically from ABV and volume, feeding straight into the prediction.

Sources

  1. [1] MHLW e-healthnet, "Absorption and breakdown of alcohol" (Japanese)
  2. [2] MHLW e-healthnet, "Blood alcohol concentration" (Japanese)
  3. [3] Suntory, "What is intoxication?" (stages of intoxication, Japanese)
  4. [4] Watson PE, Watson ID, Batt RD. Total body water volumes for adult males and females from simple anthropometric measurements. Am J Clin Nutr. 1980;33(1):27–39. (basis for estimating alcohol's distribution volume from body measurements)
  5. [5] Forrest ARW. The estimation of Widmark's factor. J Forensic Sci. 1986 (the women's formula, as re-derived by Searle 2014).
  6. [6] Jones AW. Evidence-based survey of the elimination rates of ethanol from blood. Forensic Sci Int. 2010 (the clearance rate β and its person-to-person spread).
  7. [7] Veasey et al. 2020, PMC7185312 (how food state changes the time for blood alcohol to reach its peak).

For exactly which equations and primary sources Nomicho uses to compute this, see the methodology.

This article is general information, not medical or legal advice. The chart is a conceptual illustration, not a specific person's values.