Every major grader publishes centering tolerances — the left/right and top/bottom ratio your card needs to hit for a given grade. The headline numbers look similar, but each grader rolls them up differently: PSA assigns one number, BGS gives you four subgrades, CGC adds a separate Pristine tier, and TAG returns a measured score on a 1–1000 scale.
The table below shows the worst-axis tolerance each grader publishes per grade. “Worst-axis” means: whichever of L/R or T/B is more off-center counts.
Front centering tolerance
| Grade | PSA | BGS | CGC | TAG |
|---|---|---|---|---|
| 10 | 55/45 | 50/50 → 55/45* | 55/45 (60/40 GM) | 53/47 |
| 9.5 | — | 60/40 | 60/40 | 58/42 |
| 9 | 60/40 | 65/35 | 65/35 | 62/38 |
| 8 | 65/35 | 70/30 | 70/30 | 68/32 |
| 7 | 70/30 | 75/25 | 75/25 | 74/26 |
* BGS 10 (“Pristine”) requires 50/50 centering; BGS 10 (“Gem Mint”) is up to 55/45. The starred row shows both.
Back centering tolerance
Back-of-card centering tolerances are looser across the board. The back rarely caps a grade unless it’s significantly off-center on its own.
| Grade | PSA | BGS | CGC | TAG |
|---|---|---|---|---|
| 10 | 75/25 | 70/30* | 75/25 | 70/30 |
| 9.5 | — | 80/20 | 80/20 | 78/22 |
| 9 | 90/10 | 85/15 | 85/15 | 84/16 |
| 8 | 90/10 | 90/10 | 90/10 | 88/12 |
How each grader works
PSA
Professional Sports Authenticator
The largest grader by volume. Single-number scale (1–10), no subgrades. PSA 10 caps centering at 55/45 front and 75/25 back.
BGS
Beckett Grading Services
Best-known for the gold "Black Label" 10. Uses 4 subgrades — Centering, Corners, Edges, Surface — averaged to the final grade. Centering for a 10 is essentially perfect.
CGC
Certified Guaranty Company
Tightly comparable to PSA on centering, plus a separate "Pristine 10" grade that requires near-perfect 50/50 centering. Faster than PSA, cheaper than BGS.
TAG
Technical Authentication & Grading
AI-graded on a 1–1000 numeric scale, then mapped to the familiar 1–10 view. Most transparent of the four — each card returns measured centering values you can verify yourself.
Why centering matters at all
Centering is one of the four pillars of a card grade — corners, edges, surface, and centering. It’s the most binary of the four: a card with otherwise perfect corners + edges + surface gets capped at a lower grade just because it’s off-center. And unlike the others, centering is fully measurable — you can see whether a card meets the tolerance before you ship it.
That measurement is what this tool exists for. Drop a card photo in, see the ratio, and decide whether the grader is going to give you a 10 or a 9 before you spend $25 finding out.