Card Centering Guide

Centering refers to how evenly the printed artwork sits within the card's coloured border frame. On a Pokemon card the coloured band around the artwork - the yellow border on a Pikachu card for example - should ideally look exactly the same width on all four sides.

When a card comes off the printing press, the artwork is sometimes cut slightly off centre. This means the image shifts in one direction - left, right, up or down - which makes the border on that side narrower and the border on the opposite side wider.

Think of it like a photo inside a picture frame. When the photo is perfectly centred, the gap around it looks equal on all four sides. If the photo slides left, the left gap shrinks and the right gap grows. On a Pokemon card that gap is the coloured border - the yellow band around the artwork. Centering measures how even that border is on each side.

Why does this matter for collectors? Because PSA and other grading companies measure the centering ratio on every card they grade. The further the card is from perfect 50/50 centering, the lower the centering sub-grade - and a low centering sub-grade can drag the entire final grade down even if the rest of the card is flawless.

Even a perfectly mint card with sharp corners and no scratches can receive a lower grade if the centering is off. Centering alone can be the difference between a PSA 10 worth thousands and a PSA 8 worth a fraction of that.

Before you can measure centering you need to understand the three distinct zones on any Pokemon card. Every card - regardless of set, era or rarity - has these same three zones.

Zone 1 - The Outer Card Edge

This is the physical edge of the card - the very outside boundary. This is your starting point when measuring centering. Place the zero end of your ruler right here at this outer edge. Do not start from inside the coloured border - always start from the very outermost edge of the card.

On the Pikachu Promo card you can see a thin grey rim running around the outside of the yellow border. That grey rim is Zone 1.

Zone 2 - The Coloured Border Band

The bright coloured band that runs all the way around the card - yellow on the Pikachu card. This is the zone you are measuring. The width of this coloured band in millimetres is your border measurement.

When we talk about centering being 60/40 or 55/45 we are comparing the width of this coloured band on opposite sides of the card - left versus right, and top versus bottom.

On different card types this zone will be a different colour - blue on water types, red on fire types - but it is always the same zone to measure regardless of the card.

Zone 3 - The Inner Frame Line

The thin line where the coloured border ends and the artwork window begins. This is your stopping point when measuring. Read your ruler measurement at this inner frame line.

The distance from Zone 1 (outer card edge) to Zone 3 (inner frame line) is your border width in millimetres. This is the number you write down and use to calculate the centering ratio.

The centering ratio is expressed as two numbers that always add up to 100. The first number is always the bigger (thicker) border side. The second number is the smaller (thinner) border side.

55/45 means one side of the card has 55% of the total available border space and the opposite side has only 45%. The gap between the two numbers tells you how off-centre the card is. The bigger the gap, the worse the centering.

50/50 means both sides have exactly equal border space - this is a perfectly centred card.

55/45 means one side is slightly wider - this is the maximum allowed for a PSA 10 Gem Mint grade.

60/40 means one border is noticeably wider - this puts the card in PSA 9 territory.

70/30 means one border is more than double the other - this is a severely off-centre card at PSA 7 or lower.

Example Calculation

Imagine you measure your card and get the following readings:

Left border = 3mm
Right border = 2mm

Step 1 - Add both numbers together to get the total:
3mm + 2mm = 5mm total

Step 2 - Divide each measurement by the total and multiply by 100:
Left: 3 divided by 5 multiplied by 100 = 60
Right: 2 divided by 5 multiplied by 100 = 40

Result = 60/40 - This card is Left Heavy

This means the left border is 60% of the total border space and the right border is only 40%. This card would likely receive a PSA 9 for centering.

Quick Reference - All Ratios at a Glance

50/50 - Perfect centering. Both borders look identical. PSA 10 Gem Mint.

55/45 - Very slight imbalance. Almost impossible to see without measuring. Maximum allowed for PSA 10 Gem Mint.

60/40 - Slight imbalance. Visible if you look closely. PSA 9 Mint range.

65/35 - Noticeable imbalance. Clearly visible to the naked eye without measuring. PSA 8 Near Mint range.

70/30 - Severe imbalance. One border is almost double the other. Very obvious. PSA 7 Near Mint range.

75/25 or worse - Extreme imbalance. One border nearly gone. PSA 6 Excellent or lower.

These four terms describe which direction the card's printed image has shifted. The word "heavy" means the border on that side is thin - because the image has pushed toward that side, squeezing the border. The opposite side will have a thick border.

Left Heavy

The printed image has shifted toward the left side of the card. This makes the left coloured border thin and the right coloured border thick.

How to spot it: Look at the card straight on. The right border looks visibly wider than the left. The artwork appears to have shifted toward the left edge of the card.

What the numbers look like: Left: 60 - Right: 40

Right Heavy

The printed image has shifted toward the right side of the card. This makes the right coloured border thin and the left coloured border thick.

How to spot it: The left border looks visibly wider than the right. The artwork appears to have shifted toward the right edge of the card.

What the numbers look like: Left: 40 - Right: 60

Top Heavy

The printed image has shifted upward toward the top of the card. This makes the top coloured border thin and the bottom coloured border thick.

How to spot it: The bottom border looks visibly wider than the top. The artwork appears to have shifted toward the top edge of the card.

Important note: On all Pokemon cards the top border is naturally wider than the side borders because it includes the card name and HP area. This is completely normal. Always compare the top border to the bottom border only - never compare the top to the left or right borders.

What the numbers look like: Top: 60 - Bottom: 40

Bottom Heavy

The printed image has shifted downward toward the bottom of the card. This makes the bottom coloured border thin and the top coloured border thick.

How to spot it: The top border looks visibly wider than the bottom. The artwork appears to have shifted toward the bottom edge of the card.

Important note: The bottom border on all Pokemon cards is also naturally wider than the side borders because it includes the attack name, attack cost and stats text area. Always compare the bottom border to the top border only - never compare the bottom to the left or right borders.

What the numbers look like: Top: 40 - Bottom: 60

You do not need any specialist equipment. A millimetre ruler or a digital caliper is all you need. Here is exactly what to do.

Step 1 - Remove the Card from Its Sleeve

Take the card out of its penny sleeve or top loader before measuring. The plastic adds extra thickness around the edges which throws off your measurements. Always handle the card by its edges - never touch the surface of the card with your fingers as this can cause surface scratches.

Step 2 - Place the Card Face Up on a Flat Surface

Lay the card face up on a clean flat well-lit surface. Natural daylight or a bright desk lamp works best. Good lighting makes the coloured border very easy to see clearly. Make sure the card is completely flat with no bends or curves before you start measuring.

Step 3 - Measure the Left Border in Millimetres

Place the zero end of your ruler at the very outer edge of the card on the left side - this is Zone 1. Slide the ruler across until you reach the inner frame line where the coloured band ends - this is Zone 3. Read the millimetre value at that point. Write this number down.

Step 4 - Measure the Right Border in Millimetres

Repeat the exact same process on the right side of the card. Place the ruler at the outer right edge and measure inward to the inner frame line. Write this number down next to your left measurement.

Example reading: Left = 3.0mm, Right = 2.0mm

Step 5 - Calculate the Left / Right Ratio

Add both measurements together to get the total border width. Divide each measurement by the total. Multiply each result by 100 to get the percentage.

Example:
3.0 + 2.0 = 5.0mm total
Left: 3.0 divided by 5.0 multiplied by 100 = 60
Right: 2.0 divided by 5.0 multiplied by 100 = 40
Left / Right ratio = 60/40 - Left Heavy

Step 6 - Repeat for Top and Bottom

Measuring only left and right is not enough. You must also check the top and bottom borders separately. PSA grades all four sides and the worst direction is what determines the centering score.

A card can have perfect 50/50 left and right centering but terrible 70/30 top and bottom centering. It is absolutely essential to check both directions every single time before deciding whether to grade a card.

Best Tools to Use

Digital caliper - Most accurate. Reads to 0.1mm. Best choice for serious collectors before a grading submission.

Millimetre ruler - Good. Reads to 0.5mm. Fine for most purposes and checks.

Centering app on your phone - Uses your phone camera to estimate the ratio. Good for a quick first check but not precise enough to rely on before a grading submission.

Naked eye - Use for a quick visual check only. If the border imbalance is obvious by eye it is likely already at 60/40 or worse.

Pro Tip - Where to Place Your Ruler

Always measure at the midpoint of each side. Place your ruler halfway up the left edge when measuring the left border. Place it halfway across the top edge when measuring the top border. Do not measure at the corners. Card corners can be slightly worn or rounded which gives inaccurate readings.

PSA evaluates centering on all four sides of every card. The worst direction is what determines the centering component of the final grade. Going beyond the threshold in any single direction will cause the grade to drop - even if everything else on the card is absolutely perfect.

PSA's official standard states that the image must be centred within a tolerance not to exceed approximately 55/45 to 60/40 on the front of the card for a PSA 10 Gem Mint grade.

PSA 10 - Gem Mint

Centering requirement: 55/45 or better on both left/right and top/bottom.

What it looks like: The coloured borders look almost identical on both sides. The difference is barely visible to the naked eye even when you look closely. This is the most desirable grade and commands the highest collector value.

PSA 9 - Mint

Centering requirement: 60/40 or better on both left/right and top/bottom.

What it looks like: A slight imbalance is visible if you look closely and compare both sides carefully. One border looks slightly thinner than the other. Still a strong and valuable grade - often the best realistic outcome for many cards.

PSA 8 - Near Mint / Mint

Centering requirement: 65/35 or better on both left/right and top/bottom.

What it looks like: Clearly noticeable to the naked eye without needing to measure. One border is obviously thinner than the other. A decent grade but value is noticeably lower than a PSA 9 or PSA 10.

PSA 7 - Near Mint

Centering requirement: 70/30 or better on both left/right and top/bottom.

What it looks like: One border is almost double the other. Very obvious to anyone looking at the card. The imbalance is severe enough to significantly reduce both the visual appeal and the monetary value of the card.

PSA 6 - Excellent

Centering requirement: Beyond 70/30 in either direction.

What it looks like: Extreme off-centering. One coloured border is nearly disappearing entirely. The artwork looks like it is falling off one edge of the card. At this level grading fees may not be worth the cost of submission.

Centering Is Just One of Four Grading Criteria

PSA also grades corners, edges and surface condition alongside centering. A card can have perfect 50/50 centering but still receive a lower final grade due to surface scratches, print lines, worn corners or chipped edges. Always check all four criteria before deciding whether a card is worth submitting for grading.

Vintage Cards Naturally Have Worse Centering

Base Set and early era cards were printed with older less precise cutting machines. Off-centering was far more common in cards printed in the 1990s and early 2000s. A PSA 9 on a vintage Base Set card with 60/40 centering is often more impressive than it sounds. Do not expect the same centering standards from vintage era cards as you would from modern prints.

Always Check Centering Before Paying to Grade

Grading fees are not refundable regardless of the outcome. If your card is beyond 60/40 in either direction a PSA 10 is very unlikely. Always complete your centering check at home first. If the card fails your ruler test decide carefully whether a PSA 9 or PSA 8 outcome justifies the cost of the grading submission fee for that particular card.

Use the Eye Test First Before Getting Your Ruler

Before measuring simply look at the card under good lighting and compare the coloured borders on opposite sides. If one side clearly looks much thinner than the opposite side it is probably already at 60/40 or worse without even measuring. Only get your ruler out for cards that look close to perfect by eye - those are the ones where a precise measurement will actually make a difference to your grading decision.

Both Directions Must Pass

Many collectors check left and right centering only and forget about top and bottom. PSA will check all four sides. A card with perfect 50/50 left and right centering but 70/30 top and bottom centering will not receive a PSA 10. You must check both axes every single time without exception.