How card grading works

Practical guide

"Grading" means assigning a standardized score to a card's physical condition, usually on a 1-to-10 PSA-style scale. The goal is to make different cards comparable with a number, instead of subjective descriptions.

The four parameters

Most grading schemes — including the one we use — evaluate four separate aspects, then combine them into an overall score:

• Centering — how well the artwork is centered relative to the card's edges. A visible imbalance lowers the grade even if the rest of the card is flawless.
• Corners — how sharp the four corners are. Rounding, small creases, or wear marks on the corners are among the most common and most noticeable defects.
• Edges — the condition of the four sides: chipping, whitening (the small light-colored layer that shows when the edge's color wears off), or uneven cut marks.
• Surface — scratches, stains, fingerprints, and for foil/holo cards also foil imperfections that can be hard to spot without good lighting.

How the overall grade is calculated

The final grade isn't a simple average of the four parameters: it's typically constrained by the worst one, because a single obvious defect (e.g. a rounded corner) shapes the overall perception of the card more than an arithmetic average would. A card with perfect centering, edges and surface but one visibly damaged corner won't get a high grade just because three out of four parameters are excellent.

Why it matters so much

The condition grade is often the single biggest factor in a valuable card's resale price, alongside rarity and edition (see the guide on what a card is worth). That's why sellers of valuable cards look for a recognized grade, and buyers use it to compare different offers without having to physically inspect every card themselves.