What a centering ratio means
A centering ratio compares two opposite borders as shares of their combined width. Add the two border widths together, then express the larger one as a percentage of the total. A left border of 3mm and a right border of 2mm add up to 5mm; 3 divided by 5 is 0.60, so the card is 60/40 left to right. A perfectly centered card is 50/50.
Every card has two axes on each side: left to right and top to bottom. Grading companies care about the worse axis, because a card that is 50/50 side to side but 65/35 top to bottom still looks off-center. PSA's standards page describes centering as the difference at the most off-center part of the card, so you should measure where the border is thinnest, not where it looks average.
Throughout this guide we write ratios with the larger side first, so "lower is better": 55/45 is better centered than 60/40. If you'd rather skip the arithmetic, our card centering calculator takes four border measurements per side and tells you the ratio and the best grade each company's published standard allows.
Centering standards: PSA vs BGS vs TAG
Each grading company publishes its own centering limits. The tables below list the worst ratio each grade allows, copied from the companies' own standards pages. Grades where a company does not publish a centering figure are left out.
PSA centering standards
| PSA grade | Front (worst allowed) | Back (worst allowed) |
|---|---|---|
| 10 Gem Mint | approximately 55/45 | 75/25 |
| 9 Mint | approximately 60/40 | 90/10 |
| 8 NM-MT | approximately 65/35 | 90/10 |
| 7 Near Mint | approximately 70/30 | 90/10 |
| 6 EX-MT | 80/20 | 90/10 |
| 5 Excellent | 85/15 | 90/10 |
| 4 VG-EX | 85/15 | 90/10 |
| 3 Very Good | 90/10 | 90/10 |
| 2 Good | 90/10 | 90/10 |
| 1 Poor | approximately 90/10 | approximately 90/10 |
PSA adds a centering note: at the grader's sole discretion, a small variance may be permitted on occasion based on the card's overall eye appeal. The same page explains that eye appeal can also work against you, so a card that technically measures within a grade can still be held back if the market would see it as off-center.
BGS centering standards (Beckett)
| BGS centering subgrade | Front | Back |
|---|---|---|
| 10 Pristine | 50/50 all around | 55/45 or better |
| 9.5 Gem Mint | 50/50 one way, 55/45 the other | 60/40 or better |
| 9 Mint | 55/45 both ways | 70/30 or better |
| 8 NM-MT | 60/40 both ways or better | 80/20 or better |
| 7 Near Mint | 65/35 both ways or better | 90/10 or better |
| 6 EX-MT | 70/30 both ways or better | 95/5 or better |
| 5 Excellent | 75/25 both ways or better | 95/5 or better |
| 4 VG-EX | 80/20 both ways or better | 100/0 or better |
| 3 Very Good | 85/15 both ways or better | 100/0 or better |
| 2 Good | 90/10 both ways or better | 100/0 or offcut |
Beckett grades centering as its own subgrade, so BGS centering shows up on the label next to corners, edges and surface. Two details matter. First, the 9.5 needs one front axis at 50/50, so a card measuring 55/45 in both directions is a 9 on centering, not a 9.5. Second, Beckett describes its scale as general guidelines rather than rules, and it awards half-point grades (8.5, 7.5 and so on) for cards that sit between two levels without publishing separate centering numbers for them. Beckett's older grading scale page lists the Pristine 10 back as 60/40; the current standards page says 55/45, which is what we show.
TAG centering standards
| TAG grade | Front | Back (TCG) | Back (sports and non-TCG) |
|---|---|---|---|
| 10 Pristine | ~51/49 | ~52/48 | ~54.5/45.5 |
| 10 Gem Mint | ~55/45 | ~65/35 | ~70/30 |
| 9 Mint | ~60/40 | ~75/25 | ~90/10 |
| 8.5 NM-MT+ | ~62.5/37.5 | ~85/15 | ~95/5 |
| 8 NM-MT | ~65/35 | ~95/5 | not published |
| 7 | ~70/30 | not published | not published |
| 6 | ~75/25 | not published | not published |
| 5 | ~80/20 | not published | not published |
TAG's Pristine 10 allows only about 51/49 on the front, close to Beckett's 50/50 for a Pristine 10 and far tighter than a PSA 10. It is also the only one of the three that publishes different back limits for trading card games (Pokemon, Magic, One Piece and similar) and for sports cards, and it publishes half-grade front limits all the way down (7.5 is about 67.5/32.5, 6.5 about 72.5/27.5, and so on). TAG writes all of these as approximate tolerances.
CGC, for comparison
CGC's published scale says a Pristine 10 is 50/50, a Gem Mint 10 is not to exceed approximately 55/45 on the front and 75/25 on the back, and a Mint 9 sports or non-sports card needs 60/40 or better on the front and 90/10 on the back. For TCG cards CGC describes lower grades mainly by handling and manufacturing defects rather than by a centering number.
How to check card centering with a ruler
A millimeter ruler and good light are enough for most bordered cards. A ruler with half-millimeter marks, or a cheap digital caliper, makes small borders much easier to read.
- Lay the card flatKeep it in a penny sleeve if you like, but take it out of a toploader, which hides the edges and adds glare.
- Measure the left and right bordersMeasure from the card's cut edge to the edge of the printed image or frame, at the narrowest point of each border. Write both numbers down.
- Measure the top and bottom bordersSame method. Borders on modern cards are often only 2 to 4mm, so a 0.5mm reading error can move the ratio by several points. Measure twice.
- Work out each axisLarger border divided by the sum of both borders, times 100. Do it for left to right and for top to bottom.
- Keep the worse axisThe higher of the two numbers is your front centering. Repeat the whole process on the back.
- Compare against each gradeCheck the front and back numbers against the tables above. The card can only reach a grade where both sides pass.
Worked example 1: a ruler measurement
Front borders: left 3.0mm, right 2.0mm, top 2.5mm, bottom 2.5mm. Left to right is 3.0 / 5.0 = 60/40. Top to bottom is 50/50. The worse axis is 60/40. The back measures 70/30.
On PSA's published standards that front is right at the limit for a 9 and outside the approximately 55/45 needed for a 10, whatever the corners look like. On BGS it misses the 9 (55/45 both ways) and lands on an 8 centering subgrade. On TAG it fits a 9 Mint for both TCG and sports, since a 70/30 back is inside both 9 back limits.
How to check centering from a photo (pixel counts)
A photo is often more precise than a ruler, because you can zoom in until the border edge is obvious and count pixels instead of reading tick marks. The method is the same math with pixels instead of millimeters.
- Shoot square-onPut the card on a dark, contrasting surface and photograph it from directly above, with the phone parallel to the card. Any angle stretches the near border and shrinks the far one, which fakes an off-center reading.
- Fill the frame and avoid glareUse soft, even light. Glare on a holo or a chrome finish can hide where the print begins.
- Crop and zoomOpen the photo in any editor that shows cursor coordinates. Zoom into each border.
- Count pixelsNote the x coordinate of the card edge and the inner edge of the border on the left and right, and the y coordinates on the top and bottom. The differences are your border widths in pixels.
- CalculateSame formula as with a ruler. Pixels are as good as millimeters because only the ratio matters.
Worked example 2: a Pokemon card from a phone photo
Front, in pixels: left 46, right 38, top 40, bottom 44. Left to right is 46 / 84 = 54.8/45.2. Top to bottom is 44 / 84 = 52.4/47.6. The worse axis is 54.8/45.2. Back: left 58, right 32, so 58 / 90 = 64.4/35.6, and top to bottom is closer to even.
- PSA: the front is just inside approximately 55/45 and the back is well inside 75/25, so centering does not rule out a PSA 10. Being this close to the line is exactly where PSA's eye appeal discretion comes into play.
- BGS: neither front axis is 50/50, so the 9.5 is out. 55/45 both ways and a back better than 70/30 gives a 9 centering subgrade.
- TAG (TCG): the front misses Pristine (about 51/49) but meets Gem Mint 10 (about 55/45), and 64.4 on the back squeezes under the TCG Gem Mint back limit of about 65/35.
Same card, three different centering outcomes. That is why it pays to know which company you're submitting to before you decide a card is "10 centered."
Worked example 3: a great front with a weak back
A card measures 52/48 on the front and 80/20 on the back. On PSA, the 80/20 back fails the 75/25 limit for a 10 but fits the 90/10 limit for a 9, so centering caps it at 9. On BGS the back caps the centering subgrade at 8 (80/20 or better). On TAG, a TCG card is limited to 8.5 by the back (about 85/15), while a sports card can still reach 9 (about 90/10). Collectors who only look at the front get caught by this all the time.
Back centering: don't skip it
All three companies publish a back limit for their top grades, and the back limits are looser than the front, but not unlimited. PSA allows 75/25 on the back for a 10. BGS wants 60/40 for a 9.5 and 55/45 for a Pristine 10. TAG's TCG back limit for Gem Mint is about 65/35, tighter than the sports figure of about 70/30. Card backs often have plainer designs, which makes the borders easy to measure, so there is no excuse to skip this step.
Full-art and borderless cards
Full-art Pokemon, borderless Magic cards and many modern inserts have no plain border to measure. None of the three standards pages we checked gives a separate method for borderless cards, so treat any reading as an estimate. The practical approach is to pick a printed reference that should sit at a consistent distance from the edge, such as the inner frame line, the text box, the set symbol bar or a thin printed outline, and measure from each cut edge to that reference. Use the same reference on opposite sides, and check the back too, because many full-art cards still have a normal bordered back where centering is easy to read.
Tilt, diamond cuts and the OC qualifier
Sometimes the print is not just shifted but rotated, so one border tapers from thick to thin along its length. Collectors call this tilt or a diamond cut. Measure each border at both ends and use the thinnest point, since that is the most off-center part of the card. Beckett's scale explicitly allows very slight diamond cutting at a 7, slight at 6 and 5, moderate at 4 and 3, and noticeable at a 2, which tells you a visible diamond cut is a real problem for a high BGS grade.
PSA handles badly centered cards with qualifiers. Its standards say an off-center card will either be designated "OC" or receive a numerical grade that reflects the minimum centering allowed for that grade. A qualified grade such as "PSA 8 OC" generally sells for less than the same number without the qualifier, so it's worth knowing in advance whether your card is near the line. PSA also uses "MC" (miscut) for cards with an atypical cut for the issue, such as part of the next card showing.
When centering is the only thing in the way
Centering is a ceiling, not the whole grade. A card with perfect centering and a whitened corner is not a 10, and a card at 54/46 with flawless surface still risks a 9 if the grader judges the eye appeal harshly. Use centering as your first filter, then look at the other grading criteria: corners, edges and surface. Our guide to pre-grading cards walks through the full checklist, and PSA 10 vs PSA 9 explains why the gap between those two grades matters so much for value.
The Binder AI app can speed this up. Its grade estimate includes a centering subgrade alongside corners, edges and surface, on the PSA, BGS or TAG scale, and it has a manual centering tool where you drag the border guides yourself on borderline or full-art cards. Treat the output as an estimate, not an official grade. You can get the Binder AI app on iOS, Android or the web, and read how the scoring works in our AI card grading guide.
Once you know your centering and condition, run the numbers: is my card worth grading? covers the decision, and the grading ROI calculator compares likely sale prices against fees.
Sources, checked October 2026: PSA grading standards, Beckett grading standards, Beckett grading scale, TAG grading rubric, TAG help: how do I get a Pristine 10?, CGC grading scale.
