Pokémon Card Centering Tool — Free & Online
Centering is the number-one reason Pokémon cards miss a PSA 10. Skip the printable rulers and eyeballing — upload a photo and our free online centering tool measures your card's exact front and back centering percentages in seconds, then tells you if it's inside PSA's 10 tolerance.
- 1 Upload a card photo
- 2 Get an AI grade in ~2s
- 3 Decide what's worth submitting
Front + Back
Both Measured
Exact %
Not Guesswork
Online
No Printable Ruler
Free
To Use
Measure Centering the Way Graders Do
PSA judges centering as a left/right and top/bottom ratio. Our tool calculates those ratios automatically from a single photo — no physical ruler, no 3D-printed jig, no math.
Exact Centering Percentages
Get precise left-right and top-bottom centering ratios for the front and back of your card, the same measurement graders use to assign a centering subgrade.
Online — Nothing to Print
No printable centering ruler, AliExpress jig, or STL file needed. The tool works in your browser from a photo, so you can check a card anywhere.
PSA 10 Tolerance Check
The tool tells you whether your centering falls inside PSA's strict gem-mint tolerance (roughly 55/45 front) or whether it caps the card at a 9.
Front and Back Both Count
PSA grades back centering too, and it's often worse than the front. The tool measures both so you're not blindsided after submission.
Part of a Full Grade Check
Centering is one of four grading factors. The same upload also scores corners, edges, and surface for a complete predicted grade.
Free for Any Pokémon Card
Check centering free on English or Japanese cards from any set, vintage holos to modern alt-arts, with no credit card.
Use cases
Who Uses CardMintAI?
Discover how different professionals use CardMintAI
Collectors & Hobbyists
Assess Card Conditions Before Grading
Save time and money by identifying high-value cards to prioritize for grading. Get instant AI grading to determine the potential grade of your cards before submitting them to official grading services.
Resellers & Dealers
Generate Grading Reports for Sales
Boost sales by showcasing AI-backed grading reports alongside your card listings. Provide potential buyers with detailed grading reports, increasing the credibility of your listings.
Marketplace Sellers
Integrate Grading for Product Listings
Increase buyer confidence with consistent, AI-generated grading reports. Integrate AI grading directly into your marketplace listings, allowing buyers to view card conditions instantly.
Grading Pre-Checkers
Evaluate Card Quality Before Submitting
Avoid unnecessary grading fees by assessing card condition early. Use AI to pre-check cards and get a sense of their grading potential before submitting to PSA/BGS.
Investment Groups
Track Grading History and Resale Value
Leverage historical data to identify undervalued cards with high grading potential. Monitor card grading history and predicted resale value to make informed investment decisions.
Developers & Integrators
Build Custom Grading Workflows with the API
Automate grading at scale and embed grading reports in your own platform. Use the CardMintAI API to integrate AI-powered card grading directly into your marketplace, app, or internal tools.
Popular Grading Tools
Pay Less Than a Single PSA Fee
Most collectors grade in bursts before a submission — so start with pay-once credit packs that never expire, or subscribe monthly if you grade all the time. Either way it's a fraction of one PSA fee.
Collector
- 60 gradings/month
- Batch grading (up to 10)
- API access
- Analytics dashboard
- Priority support
Master
- 150 gradings/month
- Everything in Collector
- Batch grading (up to 10)
- Dedicated support
- Custom integrations
Pay-Once Credit Packs — Never Expire
Only grade when you're prepping a submission? Skip the subscription. Buy credits once, use them whenever — they never expire and unlock full subgrade reports instantly. 1 credit = 1 grade.
Explore Credit Packs →Frequently Asked Questions
Is there a free online Pokémon card centering tool?
Yes. CardMintAI offers a free online centering tool — upload a photo of your Pokémon card and it calculates exact front and back centering percentages in seconds. There's no printable ruler or physical jig required, and no credit card to start.
How do I check the centering of a Pokémon card?
Upload a clear photo to CardMintAI's centering tool. It measures the border ratios on all four sides and reports left-right and top-bottom centering percentages for the front and back, then tells you whether the card meets PSA's gem-mint tolerance.
What centering does a card need for a PSA 10?
PSA generally requires roughly 55/45 centering or better on the front for a 10, with the back allowed slightly more tolerance. Our tool measures your card's actual ratios and flags whether centering would hold it back from a 10.
Does the card grading app measure centering automatically?
Yes. Centering measurement is built into CardMintAI's grading. Every upload returns front and back centering percentages alongside corner, edge, and surface scores, so you get a complete predicted grade, not just centering.
Do I need a printable centering ruler or tool?
No. CardMintAI replaces printable rulers, centering jigs, and STL-printed tools entirely — it measures centering from a photo in your browser, which is faster and more precise than aligning a card against a physical guide.
Check Your Card's Centering in Seconds — Free
See exact front and back centering percentages and know if your card clears PSA 10 tolerance.