Understanding Card Centering (and Why It Makes or Breaks a Grade)

Ask any seasoned collector what keeps a card from a gem-mint 10 and you will hear the same answer over and over: centering. A card can have perfect corners, clean edges, and a flawless surface, and still grade a 9 because the artwork sits too far to one side.

What centering actually measures

Centering is the ratio of border width on opposite sides of the card. Graders look at it two ways:

• Left-to-right — the width of the left border compared to the right.
• Top-to-bottom — the width of the top border compared to the bottom.

It is usually written like 60/40, meaning one side's border is 60% of the combined width and the other is 40%. A perfectly centered card is 50/50.

The numbers that matter

As a rough guide for high grades:

• 55/45 or better front and back is gem-mint territory.
• 60/40 typically caps you around a 9.
• 65/35 and worse starts pulling grades down quickly.

Vintage cards are notorious for poor centering because of how sheets were cut decades ago, which is part of why well-centered Base Set cards command such a premium.

Do not forget the back

Many collectors measure the front and stop there. Backs are cut on the same sheets and are often more off-center than the front. A 50/50 front with a 70/30 back will not earn a top grade. Always evaluate both sides.

How to check centering at home

Hold the card under even light and compare opposite borders. If you want precision, the AI in Cardemon measures centering automatically from your front and back photos and reports it as part of your sub-grades, so you do not have to eyeball ratios.

The takeaway

Before you fall in love with a card's holo shine, check the borders. Centering is the first thing a grader's eye goes to, and it is the easiest factor to evaluate before you ever submit. Scan a card in Cardemon and you will see your centering ratio in seconds.