Total energy, min voltage, peak power, continuous power — meeting or exceeding your target is ideal (more is fine, no penalty). Up to 10% under target is shown as a marginal match, worth a look. More than 10% under and the pack is excluded.
Max system voltage — at or under your target is ideal. Up to 5% over is marginal. More than 5% over and the pack is excluded outright — going over the max voltage is treated as a compatibility problem, not a small miss.
Weight, max dimension — soft comparison only. Packs over target are scored down but never excluded.
Ranking — every targeted spec contributes to the fit score. Picking a primary spec weights it more heavily (4×) but doesn’t let it override a pack that’s badly off on everything else. Specs you leave blank are shown greyed out for reference — they never affect the ranking. If a pack doesn’t report a spec you targeted, it’s kept in the results (tagged no data) and barely weighted, rather than thrown out — except total energy, which is mandatory whenever it’s targeted: no energy figure means the pack is excluded outright.
Falls short vs. meets/exceeds — when total energy is targeted, it alone decides which side a pack lands on (more energy is always “exceeds,” less is always “falls short”). Other specs can’t flip that. Picking the closest match within that side weights every targeted spec equally by default (energy included) — it’s the pack with the smallest overall distance to your targets, not the one that exceeds by the most. Packs are excluded outright if a spec they do report is clearly outside the hard limits (max voltage, or more than 10% short on a minimum).