Free collector tools
Card centering calculator
Measure a card photo or enter border widths. Get left/right and top/bottom ratios and the best listed PSA grade the centering alone allows, front and back. Free, with no account needed.
Your photo stays in this browser. No photo is uploaded. Use a straight-on photo with the card upright and all edges visible. This tool does not correct perspective or rotated cuts.
front centering
Choose this side's photo and align its lines to measure it.
back centering
Choose this side's photo and align its lines to measure it.
Measure both sides. The lower ceiling limits the combined centering check. PSA allows judgment around approximate tolerances; this calculator uses the published cutoffs without an eye-appeal allowance. It does not assign half-point grades. A missing result is not a pass.
Centering is one of four factors
A card can center for a 10 and still grade lower on corners, edges or surface. This is a measurement aid, not authentication or a grading guarantee. Estimate, not a PSA grade. Not affiliated with PSA.
Tolerances come from our PSA centering tolerances by grade guide, citing PSA's grading standards read on 2026-10-07.
The separate photo estimator includes 3 free estimates a month with a free account. Compare plans and pricing.
Centering questions
What centering do you need for a PSA 10?
PSA's published guideline is approximately 55/45 or better on the front and 75/25 or better on the back. Check both axes on each side. Centering is only one factor; corners, edges and surface can still lower the grade.
Does back centering matter?
Yes. Measure the back separately. A front within the top tolerance does not offset a back outside it. The calculator keeps separate front and back measurements.
How do I measure centering at home?
Measure opposite border widths with the same unit, or take a straight-on photo and align the outer card edges and inner printed borders. Divide the wider border by the sum of the opposing widths. Repeat for the other axis and the back.
Is my photo uploaded, and do I need an account?
No. This free calculator reads and draws your selected image locally in your browser. No photo leaves the browser, and no account is needed for this tool. The separate photo grade estimator requires a free account.
Can I use a borderless card or an angled photo?
Only measure when you can identify matching printed reference lines on opposite sides. The tool does not correct perspective, rotation or uneven cuts. Retake angled photos and treat uncertain borders as uncertain measurements, not an exact grade.