Centering is the alignment of the printed image within the card borders, expressed as a left/right and top/bottom percentage. Perfect centering is 50/50 — the borders on opposite sides are exactly equal. Centering is one of the four primary grading factors (along with corners, edges, and surface) and is often the single largest grade-cap factor for vintage cards. PSA standard for a Gem Mint 10 typically requires 55/45 or better centering, with similar but service-specific tolerances at BGS, CGC, and SGC.
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Centring, sometimes spelled centering, refers to the alignment of a card’s printed image relative to its physical edges. Perfect centring places the borders evenly on all four sides; off-centre cards show wider borders on one or more sides relative to others, a defect that originates in the printing and cutting process and cannot be remedied after the fact.
For graded cards, centring is one of the four primary grading factors alongside corners, edges, and surface. Top grades require centring tolerances of approximately 55/45 or better front and back, and gem-mint grades increasingly demand 50/50 centring. Two cards with identical surface, corner and edge condition can differ by a full grade tier solely on centring. See our primary centring entry for more on the measurement methodology and its role in card grading.