[Tools](https://cardinal-app.ai/tools/) # Card centering calculator Upload a photo of your card. Cardinal finds the card's edges and the printed border automatically; drag any corner to fine-tune, and see the left/right and top/bottom ratios and the PSA centering grade — measured by the same engine as the Cardinal app. Front photo Back photo (optional) Lay the card flat on a plain background, with a little space around it, and photograph it straight on. JPEG, PNG or WebP, up to 15 MB. Photos are processed in memory and not stored. How it works ## What the numbers mean. Centering compares the border widths on opposite sides. 55/45 left-to-right means the wider border is 55% of the two borders together. The outer lines mark the card's edge; the inner lines mark where the printed border meets the artwork frame. Automatic detection works best with a flat, straight-on photo and some background around the card. Full-art and borderless cards have no inner frame to find — place those lines by hand where the design's border would be. Very thin printed borders exaggerate small shifts. PSA's published standard for a Gem Mint 10 is about 55/45 on the front and 75/25 on the back — see [the PSA grading scale](https://cardinal-app.ai/guides/psa-grading-scale/) for every grade. Centering is one of four things a grader scores; Cardinal's [pre-grade](https://cardinal-app.ai/pre-grading/) reads all four. ## Centering is one of four. Scan your card for corners, edges and surface too. Free on iPhone and Android. --- Get Cardinal, free: [App Store](https://apps.apple.com/app/cardinal-tcg-scan-grade/id6810442266) · [Google Play](https://play.google.com/store/apps/details?id=ai.cardinal.app)