PSA 10 centering requirements
For a PSA 10, the front must be centered 55/45 or better and the back 75/25 or better. Here is what that means and how to check it before you pay to submit.
What 55/45 means
Centering compares the borders on opposite sides of the card. Measure the left border and the right border; each one's share of the two together is the ratio. A card with a 3 mm left border and a 2.5 mm right border is 3 / 5.5 = 55% on the left: 55/45. Do the same for the top and bottom. The worse of the two directions is the one that counts.
PSA reads the front and the back separately, with a much looser limit on the back.
PSA's centering table
| Grade | Front | Back |
|---|---|---|
| 10 Gem Mint | 55/45 | 75/25 |
| 9 Mint | 60/40 | 90/10 |
| 8 NM-MT | 65/35 to 70/30 | 90/10 |
| 7 NM | 70/30 to 75/25 | 90/10 |
| 6 EX-MT | 80/20 | 90/10 |
| 5 EX and 4 VG-EX | 85/15 | 90/10 |
| 3 and below | 90/10 | 90/10 |
These are the most centering each grade allows, from PSA's published grading standards. A card can grade lower for any other reason: a soft corner, a whitened edge or a scratch will cost more than centering ever gives back.
Checking yours from a photo
A ruler on a card in hand works, but a fraction of a millimetre is a point of ratio, and that is the whole window between 55/45 and 56/44. Preslab measures the borders on your photo instead: it straightens the card, finds the printed border on each side, and draws the lines it used so you can see where each one landed and drag one that sits off the border.
- Lay the card flat on a dark, plain, matte surface, out of its sleeve.
- Hold the phone straight above it, no flash, with background showing on all four sides.
- Photograph the back too: a back past 75/25 caps a card at 9 however good the front is.
What Preslab says, and what it doesn't
This estimate is from centering only. Preslab says how high your card's centering lets it grade, "up to PSA 10", never what it will grade. The reading is either inside 55/45 or past it: inside reads "up to PSA 10", and past it by any amount reads "up to PSA 9".