Weight alone tells you less than most owners assume, since a "normal" weight range for cats generally spans a wide enough band that a genuinely overweight small-framed cat and a genuinely underweight large-framed cat could both land in the same numeric range. Body condition scoring exists specifically to fill this gap.
What body condition scoring actually measures
Rather than a single number, body condition scoring is a hands-on, visual assessment using a standardized scale (most commonly 1-9, with 4-5 representing ideal) that evaluates rib coverage, waist definition from above, and abdominal profile from the side. This gives a picture calibrated to your specific cat's frame, not a population-wide average.
The three checks that make up an assessment
Ribs should be easily felt with light pressure, without a thick fat pad but without being visibly prominent either. A waist should be visible from directly above, a gentle inward curve behind the ribs. From the side, the abdomen should tuck upward rather than hang or bulge. All three together give a more reliable picture than any single check alone.
Why weight tracking still matters alongside this
Body condition scoring is somewhat coarse — it doesn't detect small changes the way a consistent weight log does. Using both together, tracking weight regularly while periodically reassessing body condition, catches trends earlier than either method alone.
Long-haired cats present a genuine assessment challenge
Visual assessment is considerably less reliable under a thick coat, making the hands-on rib check more important than the visual waist check for these cats specifically. Regular hands-on assessment matters more here than for short-haired cats where visual cues are more readily apparent.
Using this at home between vet visits
A monthly body condition check, done consistently and ideally by the same person to reduce subjective variation, gives you an early warning system for gradual weight changes that might otherwise go unnoticed until a routine annual visit reveals a more significant shift than would have been caught with more frequent home monitoring.