What it does
When a card is printed, the picture should sit in the middle, with equal border on both sides. Centring is how close it is. It is written as a split such as 55/45: the thinner border is 45% of the two borders together, the wider one is 55%.
Type the four border widths for the front, and optionally the back. The tool gives the left/right and top/bottom splits and draws the card with the picture where it really sits. It never says what grade a card would get, because every grading company sets its own centring limits and also looks at corners, edges and surface. See what the grade words mean with grade scale.
How to use it
- Measure the border on each side of the printed picture, in mm with a ruler or in px on a straight scan or photo.
- Type left, right, top and bottom. Fill in the back too if you want it.
- Read the splits and look at the drawing.
What each setting does
- Units: a label only; the split is a ratio, so any unit works if you keep to it.
- Left, Right, Top, Bottom: the border widths. Blank means not measured.
- Back: optional second set.
Worked example
Left 3 and right 2: the borders add to 5, and 3 ÷ 5 = 60%, so the split is 60/40. Top 2.5 and bottom 2.5 gives 50/50, perfectly centred up and down.
FAQs
Which side goes first in 60/40? The larger border always comes first, whichever side it is on. Check the drawing to see which way the picture leans.
What split is good enough? That depends on the company and on the grade you want. Look at the grading company’s own published limits.
How do I measure accurately? Place the card square on a flat scan and measure on the image, or use callipers. Keep the card straight.
Is anything sent anywhere? No. It all runs in your browser.
Where the numbers come from
- Centring split: the larger border divided by the two borders added together, rounded to a whole per cent. Standard method used by card collectors.
- Drawings are fibub's own. Grading companies publish their own centring limits; check the company's own page.
Standard scientific values, such as constants, atomic weights and melting points, are facts found in every textbook; we name where ours were checked. If you are an author or publisher and want a value, a credit or a table changed or removed, tell us and we will act quickly.
Last updated 2026-11-10.