Pre-grade your card
Upload a clear photo of your card front. We'll run a heuristic centering, corners, edges and surface scan and return an estimated PSA-style grade in seconds.
How does pre-grading work?
We run a lightweight computer-vision pipeline on your photo and combine four PSA-style sub-scores. Useful before shipping a card to a real grader — and free.
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Centering: how evenly the card sits inside its frame. PSA's ladder: 0% offset = grade 10, 5% = 9, 10% = 8, 15% = 7, and so on. The worse axis (horizontal vs vertical) sets the cap.
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Corners: sharpness of all four corner squares vs the artwork center. Whitened or rounded corners drop the score; clean printed corners stay high.
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Edges: continuity of the outer border line on all four sides. Nicks, whitening or low contrast break the line and pull the score down.
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Surface: scratches, glare, holo sparkle and overall print quality. We dock points only when glare sits on top of artwork or text.
PSA half-grade ladder
- PSA 10 (Gem Mint) — flawless print, perfect corners and edges, no surface defects.
- PSA 9 (Mint) — one minor flaw allowed: 60/40 centering, slight surface mark or a faint corner touch.
- PSA 8 (NM-MT) — minor wear: light scratches, very small whitening on corners, 70/30 centering.
- PSA 7 (Near Mint) — visible wear: light scratches, minor edge whitening, off-centre print.
- PSA 6 (EX-MT) — clearly played: noticeable whitening, scratches, but no creases or holes.
- PSA 5 (EX) — well-loved condition. Multiple defects but no major creases.
- PSA 4 or below — heavy play. Creases, deep scratches, missing colour, possibly altered. Most value is at PSA 7+; PSA 9 and 10 carry the strongest premium.
Limitations of a one-photo estimate
- Only the front: we can't check the back for surface defects or print lines.
- Holos are harder: foil sparkle interferes with corner sharpness measurement. v0.2 corrects for this, but expect more noise on holos than on flat-printed cards.
- Lighting matters: harsh side-light or yellow indoor bulbs will lower the surface score. Shoot in even daylight when possible.
- No weight or thickness check: PSA, BGS and CGC physically inspect counterfeit signals we can't see in a photo.
Heuristic v0.2 — not a replacement for real grading
This is an automated estimate from a single front photo. Expected noise is ±1.5 PSA grades. Do not use it as the sole basis for buying, selling or pricing — for that, submit to PSA, BGS or CGC. We accept no liability for grading or pricing decisions made from this tool.
Help us train the v1 model
Have a PSA, BGS or CGC graded card? Send us the front photo plus the grade slip to feedback@collectorstashmarket.com and you'll help calibrate the v1 ML model that replaces this heuristic.