The Autonomic Score & Grade Bands: One Number, Explained

From a dozen numbers to one

A single HRV reading throws a lot of numbers at you: RMSSD, pNN50, SDNN, total power, the LF and HF peaks, the LF/HF ratio. Each one is meaningful, but staring at six or seven metrics every morning is a fast way to stop tracking altogether. So the app does what a good coach does, reading all of them and giving you one number and one color: a 0–100 readiness score and a grade band. That score is the source of every colored tint you see elsewhere in the app, and this article is the key to reading all of them.

The idea is simple in spirit. Treat the score as your quick answer to “how recovered am I today?”, glance at the color, and get on with your day. Then, when the number surprises you (a low grade, or a suspiciously high one) you drill into the individual metrics to see why. The score is the headline; the metrics are the story.

The grade vocabulary

Every metric and every overall reading gets sorted into one of six grades, running best to worst, with one special seventh band standing off to the side.

The six ranked grades follow a traffic-light logic: Excellent and Good in green, Moderate in yellow, Compromised in orange, and Bad then Crash in deepening red. Greener means more recovered; redder means more strained.

The seventh, Warning, is different. Rendered in violet, it isn’t a rank: it’s a too-high flag. When a readiness score climbs far above your normal, that usually isn’t a sign of extraordinary fitness. More often it means something is off: an oncoming illness dropping your heart rate, a measurement artifact, or an unusually quiet reading that the math over-rewards. The Warning band exists to stop you from celebrating a number that deserves a second look instead. This mirrors the “blue zone” concept used on individual metrics, where a value can be too high as well as too low.

How the readiness score is built

The overall score (the HRV composite) is a weighted blend of the reading’s key metrics. Each metric is first graded on its own scale (the same scales covered in the individual articles), and then those grades are combined with weights that reflect how much each one tells you about recovery. Crucially, the app uses two weightings, because a relaxed reading and a paced-breathing reading are answering slightly different questions.

For an unstructured HRV reading (you sitting or lying quietly, breathing however you breathe) the weighting leans on the vagal metrics:

For a paced / breathing reading (where you followed a guided pace) the weighting shifts toward the peaks, because now the question is partly did the breathing actually drive the rhythm?

Notice what changes: the paced weighting adds the HF peak and raises the LF peak’s weight, because in a paced session those peaks reveal whether you actually hit your target pace and pulled power into the resonance zone. The vagal metrics still lead (RMSSD stays the single heaviest input in both) but the frequency picture earns more say when you’re breathing on purpose. The weighting rationale traces back to the same framework laid out in the Shaffer and Ginsberg (2017) overview and the Laborde et al. (2017) methodological guidance.

The readiness score bands

Here’s how the 0–100 composite maps to grades. Note the violet Warning sitting above Excellent, not below Crash:

Try a score against the same bands the app uses:

Reading the score well

The score is designed to be glanced at and then trusted only as a trend. A few habits keep it honest:

• Read it against your own baseline. A 62 that’s well above your usual is a great day; the same 62 after a run of 75s is a dip worth noticing. The absolute number matters less than where it sits relative to you.
• Let a surprise send you into the metrics. When the score is low, open the reading and see which metric dragged it: a collapsed RMSSD tells a different story than a wandering LF peak. When it’s a violet Warning, check the raw tachogram for artifacts before assuming anything.
• Follow the line, not the dot. One reading is weather; the multi-week trend is climate. Recovery, covered in recovery from post-viral dysautonomia, shows up as a slowly rising floor, not a single perfect morning.

Because it distills everything into one trackable number, the readiness score is also the easiest thing to bring to an appointment. A clean chart of your score over months (with the metrics behind it available when asked) turns a vague “I’ve been feeling off” into something a clinician can actually work with, which is the whole point of turning your data into a doctor conversation. For the bigger picture of how the app captures, analyzes and acts on these readings, see the app overview.

The bottom line

The autonomic score is the app’s way of turning a scatter of HRV metrics into one honest answer: a weighted 0–100 readiness number and a color grade from Excellent to Crash, with a violet Warning reserved for readings too high to trust at face value. Unstructured and paced readings weight the metrics a little differently, but RMSSD leads both and the logic is the same: combine the pieces, then let you drill in for the why. Read it against your own baseline, follow the trend rather than the day, and use a surprising score as a prompt to look closer, not a verdict to take at face value.