Master the 4 key factors that determine card value: Centering, Corners, Edges, and Surface. Then practice with our free AI grading tool.
Every professional grading service evaluates these same criteria
Measures if the image is evenly positioned on the card. Perfect centering is 50/50 on all sides.
60/40 or better on front, 75/25 on back
65/35 or better on front
70/30 or better on front
Sharp, pristine corners are essential for high grades. Even slight wear significantly impacts value.
All four corners sharp and intact
Slight touch of wear on 1-2 corners
Minor wear on corners, no rounding
Clean, sharp edges without chipping, whitening, or fraying. Use magnification to spot edge issues.
No visible edge wear under magnification
Minor edge wear visible only under close inspection
Slight edge wear visible to naked eye
The card face should be free from scratches, print lines, stains, and other surface defects.
Flawless surface with no imperfections
One minor surface flaw allowed
Light surface wear or minor print defect
Pro Tip: Use good lighting and magnification. Many surface defects are invisible to the naked eye.
Quick reference guide for all PSA grades
Virtually perfect card
Only minor flaws under scrutiny
Near Mint to Mint condition
Minor wear visible
Excellent to Mint
Obvious wear but no creases
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Corners are often considered the most critical factor. Even a perfect card with one poor corner cannot achieve a PSA 10. However, all four factors (centering, corners, edges, surface) work together to determine the final grade.
Yes! Pre-grading your collection helps you decide which cards are worth professional grading. SnapGradeAI provides instant AI-powered pre-grading to help you make informed decisions.
A 10x loupe or magnifying glass is standard for detailed inspection. Many collectors use 10x-30x magnification to spot edge wear and surface defects that are invisible to the naked eye.
Significantly. A card with perfect corners and surface but poor centering (70/30 or worse) will typically grade PSA 7 or lower. Centering is especially important for modern cards where other factors are often mint.