How to Check Card Centering (PSA 9 vs PSA 10 Explained)
The difference between a PSA 9 and a PSA 10 often comes down to fractions of a millimeter. Here's how to spot it.
The jump from a PSA 9 to a PSA 10 is often the single biggest value leap in a card's grade — and centering is frequently the deciding factor. Here's how to check it properly before you submit.
PSA 9 vs PSA 10: The Centering Difference
While PSA evaluates centering, corners, edges, and surface together, centering tolerances are publicly understood and easy to measure at home:
That means a card just a few percentage points off can be capped at a 9 no matter how perfect the corners and surface are.
How to Measure It Yourself
- Place the card on a solid background that contrasts with the card's outer border.
- Measure the left and right border widths, then the top and bottom.
- Divide the smaller border by the sum of both opposing borders.
- Compare your ratio against the PSA thresholds above.
The Problem With Eyeballing It
The human eye is surprisingly bad at judging small border differences, especially on cards with busy designs or thin borders. A card that looks "pretty centered" can easily be 62/38 — outside PSA 9 territory.
Let the app do the measuring
MintySlab uses computer vision to detect your card's edges and calculate exact centering ratios in seconds. It even corrects for slight skew when the card isn't perfectly square to the camera, so your measurement reflects the card — not your camera angle.
Check Before You Submit — and Before You Buy
With MintySlab+, you can also scan listings (including eBay) to check a card's centering before you purchase it, so you're not paying a premium for a card that won't grade the way you hoped.
Stop guessing — let MintySlab measure centering for you. Scan Before You Slab.