TAG — Technical Authentication & Grading — is the newest of the big four graders and the first to publish measured centering values on every slab. Their grade is a number from 1 to 1000, mapped to a familiar letter scale (10, 9.5, 9, etc.) for buyers used to PSA/BGS/CGC.
The big difference: TAG uses computer vision + machine learning instead of human graders. That means more consistency between cards, but it also means the algorithm can be tougher on certain defects (foil scratches, faint print lines) than a human eye would be.
Centering tolerance by grade band
| Numeric | Letter | Front | Back | Notes |
|---|---|---|---|---|
| 950–1000 | Pristine 10 | 53/47 | 70/30 | Near-perfect centering. |
| 900–949 | 10 | 55/45 | 72/28 | Standard Gem Mint. |
| 850–899 | 9.5 | 58/42 | 78/22 | |
| 800–849 | 9 | 62/38 | 84/16 | |
| 700–799 | 8 | 68/32 | 88/12 | |
| 600–699 | 7 | 74/26 | — |
Tolerances above are typical thresholds — TAG’s algorithm scores per-attribute and the centering tolerance shifts a few points per card based on artwork.
Why the 1–1000 scale matters
PSA gives you a 10 with no detail. BGS gives you four subgrades. TAG gives you the actual measurements — distance from print to edge in millimeters, scratch counts, corner sharpness scores, the works. For buyers and resellers, that transparency is a real advantage: you can verify the grade yourself instead of trusting the slab.
TAG drawbacks
- Market premium: PSA 10s still trade higher than TAG 10s on most cards today — the market is catching up but not equal yet.
- Holo surface: the algorithm is unforgiving on micro-scratches in foil that a human grader would let slide.
- No subjectivity: beautiful eye-appeal doesn’t lift a TAG grade. If your card looks better than it measures, PSA or BGS is the play.