Card centering calculator
Centering is the one attribute you can measure at home. This tool converts your measurements into the grade ceiling PSA's published tolerances allow — it does not predict a grade, and nothing is sent anywhere.
Enter the border widths in millimetres and the calculator returns the centering percentage on each axis and the best PSA grade that centering alone permits. Everything runs in your browser; no measurement leaves the page.
Front, left to right
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Front, top to bottom
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Back, left to right
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Highest grade centering allows
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PSA centering tolerance by grade
These are the numbers PSA publishes in its grading standards, read on 21 August 2026. PSA adds that a small variance may be permitted on occasion, at the grader's sole discretion, based on the card's overall eye appeal. Other companies set their top tolerance tighter — at BGS, CGC and SGC the Pristine grades start at 50/50.
| Grade | Front | Reverse |
|---|---|---|
| PSA 10 Gem Mint | 55/45 | 75/25 |
| PSA 9 Mint | 60/40 | 90/10 |
| PSA 8 NM-MT | 65/35 | 90/10 |
| PSA 7 NM | 70/30 | 90/10 |
How to measure without special equipment
Put the card on a flat surface under even light and measure the printed border, not the card edge, on all four sides. A digital caliper is ideal; a millimetre ruler and a photo zoomed on a phone is good enough to tell a 55/45 card from a 70/30 one. Measure the same feature on both sides of an axis — inner edge of the border to the card edge — or the ratio will be wrong in a way that looks plausible.
One caution specific to modern cards: full-art and textured cards often have no symmetrical border to measure at all. On those, centering is judged against the design, and no home measurement will match what a grader does.
Centering is a ceiling, not a grade
A card inside the 55/45 tolerance is not a 10 — it is a card whose centering does not stop it from being one. Corners, edges, surface, print quality and gloss are graded separately, and any one of them can take the card down several points. Use the ceiling to decide what to check next: if centering already caps the card at a 7, the rest of the inspection can be short, and so can the decision about whether grading is worth it at all.
Related pages
Fees and turnaround by grader are in the grading cost comparison; the arithmetic of whether to submit at all is on the grading ROI calculator. For the condition side of the same judgement, the condition guide covers the marketplace scale that applies to raw cards, and what a card is worth puts both in the context of price.
Frequently asked questions
How is card centering measured?
Measure the border on each side of the card, then express the wider border against the narrower one as a percentage pair. A card with a 2.0 mm left border and a 1.5 mm right border is centered 57/43 on the horizontal axis. Both axes are judged separately.
What centering do you need for a PSA 10?
PSA requires centering within approximately 55/45 on the front and 75/25 on the reverse for a Gem Mint 10. Both the left-right and top-bottom axes must sit inside that tolerance, and PSA notes a small variance may be allowed at the grader’s discretion for overall eye appeal.
Does back centering matter?
Yes, and it is the tolerance collectors forget. PSA allows approximately 75/25 on the reverse for a 10 and 90/10 for a 9 and an 8. A perfectly centered front will not rescue a back that sits outside those numbers.
Is this calculator a grade prediction?
No. It shows the highest grade centering allows, which is a ceiling, not a forecast. Corners, edges, surface, print quality, staining, gloss and eye appeal are all judged separately and can pull the grade down from that ceiling.
TCG Valuer is an independent site and app. Not affiliated with, endorsed by or sponsored by Nintendo, The Pokémon Company, PSA, Beckett, CGC or SGC. Product names are used descriptively to identify the cards and services being discussed.