What an AI grader actually checks
Every grading company scores the same four things: centering, corners, edges and surface. A human grader does it with a loupe and years of reference cards; the AI does it by comparing your photos against the patterns that separate a Gem Mint corner from one with a touch of white. SnapCard reports the estimate on the PSA scale because that is the scale most sold-price data is quoted in, which makes the raw-versus-graded comparison meaningful.
The estimate is only as good as the photos. Glare hides surface scratches, a tilted card fakes off-centering, and a dark room softens the corners. The app guides the capture, but a card photographed under a lamp will always read better than one photographed on a couch.
| Criterion | What graders look for | Common PSA 10 killer |
|---|---|---|
| Centering | Border width left/right and top/bottom | Worse than roughly 55/45 on the front |
| Corners | Sharp points with no whitening or dings | A single soft or frayed corner |
| Edges | Clean, uniform cut with no chipping | Chipping on dark-bordered cards |
| Surface | No scratches, print lines, dents or stains | Print lines and light scratches under glare |
