Got a meter? A real reading beats any AI guess — and the battery knows it.
The Ketosis Battery normally infers ketosis from your food. But if you test with a meter, you can log the actual number — and a real measurement overrides the estimate, because hard data beats a well-educated guess every time.
Ketone logging is tucked away by default so it doesn't clutter things up for people without a meter. To switch it on, head to Profile → Preferences and enable "I have a ketone meter". That adds Log Ketones to your quick-action menu.
The gold standard. Enter your meter's reading in mmol/L (0.0–8.0). The optimal ketosis range is shown right under the field: 0.5–3.0 mmol/L.
Using strips? No squinting at decimals — tap the preset that matches your strip colour: Negative, Trace, Small, Moderate, or Large. We convert it to a blood-equivalent figure for you — see what your strip is worth below, because it's probably less than you'd assume.
Breath analyser? Switch to the Breath tab and enter the reading in PPM. A typical ketosis range is roughly 2–40 PPM.
Ketone readings appear in your diary with a little droplet icon. Tap one to edit it, or use the red Delete Measurement button (it'll ask you to confirm first).
For blood ketones (mmol/L), the rough guide the app uses:
Log a few and the Stats screen tracks your average, peak, and latest, with the optimal band marked on the chart.
Those thresholds above are for blood. A urine strip doesn't measure the same thing — blood meters read BHB, strips read acetoacetate, and the two are related but not equal. So we convert your strip level to a blood-equivalent before it goes anywhere near your score:
| Strip reads | Counted as (BHB-equivalent) | Which means |
|---|---|---|
| Negative | 0 mmol/L | No ketones detected |
| Trace | 0.2 mmol/L | Below the nutritional-ketosis line |
| Small | 0.5 mmol/L | Just into ketosis |
| Moderate | 1.3 mmol/L | Solidly in range |
| Large | 2.5 mmol/L | Strong signal, still short of the top of the band |
Because clinically it isn't. Trace urine ketones turn up in people who aren't doing keto at all — overnight, or when they're a bit dehydrated. Reading a purple-ish tinge as proof of ketosis is the single most common way a strip misleads people, so we don't do it.
As you become keto-adapted your body wastes fewer ketones, so it excretes fewer of them. A long-term keto veteran's "trace" can reflect a higher blood level than a beginner's "large". That's a limit of the technology, not of the app — it's why a urine reading counts for less than a blood one when your battery is worked out, and why strips are best read as a rough yes/no rather than a score.
A logged reading doesn't just sit there looking pretty. The Ketosis Battery leans on it heavily:
KetoLens works perfectly well on food logging alone — most people never test. Ketones are there for the data nerds and anyone who wants to remove the guesswork. Totally optional.