Set up your own AI grading tool today with the same engine grading 3.8k+ grades served.
Get API accessMasterGrade Grading Engine API
Grade cards with AI in your own product.
Embed our AI grading engine — the same engine grading 3.8k+ cards a month — in your shop, app, or marketplace. JSON in, grade + sub-grades + estimated values out. Ship in an afternoon.
curl -X POST https://mastergrade.ai/api/v1/grade \
-H "Authorization: Bearer mg_live_YOUR_KEY" \
-H "Content-Type: application/json" \
-d '{
"frontImage": "data:image/jpeg;base64,/9j/4AAQ...",
"backImage": "data:image/jpeg;base64,/9j/4AAQ..."
}'How it works
From upload to grade in three calls.
Upload a card image
POST a base64-encoded JPEG or PNG to /api/v1/grade. Front image required, back image optional but recommended for centering and edges.
We return JSON
Overall grade, four PSA-style sub-grades with reasoning, card identification, estimated PSA-10 / 9 / 8 / raw values, and authenticity signal. Typical latency 6–9 seconds.
Display anywhere
Render the grade on your listing page, your checkout, your buylist intake — wherever a condition score moves the needle. Cache the response in your DB; we don't require attribution.
Request
curl -X POST https://mastergrade.ai/api/v1/grade \
-H "Authorization: Bearer mg_live_YOUR_KEY" \
-H "Content-Type: application/json" \
-d '{
"frontImage": "data:image/jpeg;base64,/9j/4AAQ...",
"backImage": "data:image/jpeg;base64,/9j/4AAQ..."
}'Response
{
"overall": 9.5,
"overallLabel": "GEM-MINT",
"centering": { "score": 9.5, "label": "Mint", "details": "55/45 L-R, 50/50 T-B" },
"corners": { "score": 9.5, "label": "Mint", "details": "Sharp on all four" },
"edges": { "score": 9.0, "label": "Near Mint", "details": "Trace whitening, top edge" },
"surface": { "score": 9.5, "label": "Mint", "details": "Holo clean, no scratches" },
"cardName": "Charizard VMAX",
"cardSet": "Shining Fates",
"cardNumber": "SV107",
"tcgType": "pokemon",
"estimatedValues": { "psa10": "$350", "psa9": "$120", "psa8": "$75", "raw": "$45" },
"recommendation": "Strong PSA 9 candidate with a shot at 10. Worth submitting.",
"confidence": 87,
"authenticity": "likely-authentic"
}Use cases
Built for shops, marketplaces, and verifiers.
Three patterns we already see partners shipping. The API is generic enough to drop into any flow that touches a card image.
Card shop checkout
Auto-grade incoming buylist cards before they hit the case. Replace ten minutes of human triage with one POST request and a saved JSON.
- →Upload front + back at intake
- →Surface PSA 10 candidates instantly
- →Track condition drift across consignment runs
Marketplace listings
Give every seller an AI-graded condition score the moment they upload photos. Reduce dispute rate, increase buyer confidence, raise GMV.
- →Sub-grades shown on every listing
- →Optional badge: "AI graded by MasterGrade"
- →Filter listings by AI grade range
Slab verification flow
Compare the AI grade against the slab number on intake to catch swaps, regrades-in-transit, and obvious mismatches before they cost you a refund.
- →Flag PSA 10 slabs that score AI 7.0
- →Build a returns triage queue automatically
- →Log every grade for audit trail
Pricing
Pay-per-grade. Bulk discounts kick in fast.
Final pricing scoped per partner. All amounts USD.
Pay-per-grade
from $0.10
per grade
Starter pricing. No commitment, no minimum.
Volume
Popular1k → 10k/mo
bulk discounts
Tiered rates kick in at 1,000/mo and again at 10,000/mo.
Dedicated infra
100k+/mo
custom
Reserved capacity, SLA, priority support, optional on-prem inference.
Model
Gemini 2.5 Pro
Tuned with PSA-equivalent scoring rubric and a 30-page grading prompt.
Lifetime grades
3.8k+
Production traffic, real cards, real collectors. Updated live.
Coverage
Multi-TCG
Pokémon, sports, MTG, Yu-Gi-Oh!, Lorcana, One Piece, and growing.
Set up your AI grading endpoint today.
One email gets you a sandbox key, sample integration code, and a scoping call. We turn most partners around inside a week.