How to Read Centering Ratios for PSA Grades
How to calculate card centering ratios, understand PSA’s published 55/45 Gem Mint 10 front standard, and use the result before a submission.
PSA centering ratios: the direct answer
PSA's published Gem Mint 10 standard calls for centering of approximately 55/45 or better on the front and 75/25 or better on the reverse. PSA notes that its graders may allow a small variance based on the card's overall eye appeal. PSA still makes the final decision after inspecting the physical card.
This makes 55/45 a useful pre-submission target, not a guarantee of a PSA 10. Corners, edges, surface, print defects, and eye appeal also affect the final grade.
Source checked August 4, 2026: PSA grading standards.
What 50/50, 55/45, and 60/40 mean
A centering ratio compares two opposite borders. The larger figure is written first.
| Ratio | What it means | PSA context |
|---|---|---|
| 50/50 | Equal borders | Ideal visual balance |
| 55/45 | One border is modestly wider | PSA's published approximate front standard for Gem Mint 10 |
| 60/40 | One border is noticeably wider | PSA's published approximate front standard for Mint 9 |
