Headroom is the score distance from the current score to the next break above it. Every tier has exactly one natural next target, so headroom is a single number per trait.
For a given score on a trait, headroom is the difference between the score and the next break above it on that trait. Headroom is reported on the 0–100 scale and is always non-negative. When the current tier is the highest tier, headroom is 0. When confidence is low, headroom is null.
The target break is determined by the current tier. Each tier has exactly one next milestone:
| Current tier | Target break | Headroom |
|---|---|---|
| Weak | developing | Distance to escape the negative distribution |
| Developing | solid | Distance to reach the positive distribution |
| Solid | strong | Distance to reach the top quartile |
| Strong | — | 0 |
| null | — | null |
Table 1. The next target for each tier. Tier assignment determines target; no configuration is required.
A score card's composite row reports headroom as the maximum per-trait headroom across the traits being scored. The composite is a harmonic mean (see composite), so the trait with the largest headroom is the one whose improvement would move the composite most. Composite headroom therefore identifies the bottleneck trait.
Per-trait headroom expresses how far a score is from the trained boundary of the next tier, in score points. It does not express how much additional effort is required — effort depends on the content, not on the number. The headroom value is an indicator of distance, not a forecast.
Composite headroom points at a trait, not at a score. Reducing the composite's headroom requires moving the specific trait it identifies; raising a non-bottleneck trait does not change the composite's headroom.
There is no break above strong, so Strong-tier scores report headroom as 0. This is distinct from a null headroom (§4.2): zero means "already at the top tier," not "cannot tell."
When confidence is low, the tier label is withheld and headroom is reported as null. The tier boundaries are unreliable in this regime, so a concrete distance to them would be misleading.