PSA — Professional Sports Authenticator — is the largest third-party grader by volume. They use a single 1–10 grade (with half-points like 1.5–9.5 in rare cases) and don’t publish individual centering, corner, edge, or surface subgrades. The final grade is determined by the worst attribute — if centering caps you at an 8, you’re an 8 regardless of perfect corners and edges.
Front centering tolerances
| Grade | Name | Front | Back | Notes |
|---|---|---|---|---|
| 10 | Gem Mint | 55/45 or better | 75/25 or better | Combined with sharp corners, perfect edges, and a clean surface. The most-requested grade and the hardest to hit. |
| 9 | Mint | 60/40 | 90/10 | A single minor flaw (faint print line, ~2mm whitening) won't drop you here. |
| 8 | Near Mint–Mint | 65/35 | 90/10 | Light wear on edges/corners + slightly off-center. |
| 7 | Near Mint | 70/30 | 90/10 | Visible wear but no major defects. |
| 6 | Excellent–Mint | 75/25 | — | Eye-noticeable centering issues; commonly returned grade for vintage. |
| 5 | Excellent | 80/20 | — | Heavy centering issues; commonly the floor before PSA stops checking centering strictly. |
Tolerances are the “worst-axis” max. A card at 53/47 left-right and 50/50 top-bottom passes the PSA 10 bar at 55/45.
How PSA actually measures centering
PSA graders measure the distance from the printed border edge to the card edge — not from the card art. The printed border is whatever colored frame sits inside the white border (or inside the cardboard edge directly on borderless cards).
A 55/45 measurement means the printed border on one side has 55% of the total border width, the other side has 45%. For a standard 63×88mm Pokemon card with ~3mm borders, that translates to a difference of about 0.6 mm between the two sides — visible to the eye but not glaring.
What PSA doesn't tell you
Because PSA doesn’t publish subgrades, two PSA 9 cards can be wildly different in centering quality — one could be a near-10 sitting at 56/44 with a tiny corner ding, another could be at 65/35 centering with perfect corners. Both read “PSA 9” on the slab.
If you’re buying graded singles, our centering tool works on raw photos AND through-the-slab photos — measure the card before paying a 9.5/10 premium and you’ll catch inflated grades fast.