Inspiration
As a trading card collector, I noticed a major pain point: getting cards professionally graded takes weeks or months and costs $20-50 per card. I wondered if AI could democratize this process, making grading instant, accurate, and accessible to every collector. I wanted to build something that would help collectors authenticate their cards, organize their collections, and connect with the community, all while making the experience fun and engaging.
What it does
GSA (Global Slab Authority) is an AI-powered (Gemini) platform that grades trading cards in under 5 seconds. Users upload photos of their cards, and our AI analyzes four key factors: centring, corners, edges, and surface condition. The system provides detailed subgrades and generates beautiful digital slabs with holographic effects and QR code verification.
Beyond grading, GSA offers portfolio management tools to organize collections, a social feed to share cards with other collectors, and a gamified experience with 50+ achievements and leaderboards. Users can showcase their best cards, track their collection progress, and compete for rankings across multiple categories.
How I built it
I built GSA using a modern full-stack architecture. The frontend uses React with TypeScript for type safety and Tailwind CSS for styling. The backend runs on Node.js with Express, connecting to a Firebase Firestore database for data persistence.
The AI grading engine is the heart of the system. I used Gemini 3 Pro to analyze card images, detecting imperfections in corners, measuring centring accuracy, identifying edge wear, and assessing surface scratches. The model outputs confidence scores and detailed subgrades for each criterion.
I integrated real-time features for notifications and live leaderboard updates. The digital slab generator uses Canvas API to create animated, shareable card images with professional PSA/BGS-style layouts.
Challenges I ran into
Cards vary dramatically in lighting, angles, and background conditions. I spent considerable time collecting diverse data and tuning Gemini's prompt to handle real-world scenarios. Achieving 99%+ accuracy required multiple iterations and careful tuning.
Another challenge was designing an intuitive grading scale that aligned with industry standards (PSA/BGS) while remaining easy to understand. I had to balance technical precision with user-friendly presentation.
Accomplishments that I'm proud of
I'm incredibly proud of achieving sub-5-second grading times with high accuracy. The AI model reliably detects even minor imperfections that would affect a card's grade.
The digital slab design exceeded our expectations; the holographic effects and animations make graded cards feel premium and shareable. The gamification system has been especially rewarding to build, with achievements ranging from "First Grade" to "Legendary Whale."
I'm also proud of building a complete, polished platform in a hackathon timeframe, including authentication, database architecture, responsive design, and real-time features.
What I learned
This project taught us valuable lessons about computer vision and Generative AI. I learned how to handle inconsistent input data and optimize prompts.
I gained experience with real-time web technologies, particulary Nest.JS and React. I also learned about designing gamification systems that keep users engaged without feeling gimmicky.
On the product side, I learned the importance of user feedback loops; even small UX improvements in the upload flow dramatically increased completion rates.
What's next for GSA - AI-powered trading card grading
I plan to expand our AI capabilities to support more card types beyond Pokémon, including sports cards, Magic: The Gathering, and Yu-Gi-Oh. I want to add bulk grading features for collectors with large collections.
I'm exploring partnerships with collectors and content creators to build our community. I also plan to implement machine learning feedback loops where users can report grading inaccuracies, helping Gemini continuously improve.
Future features include AR visualization (view your graded cards in augmented reality), smart collection recommendations based on what you already own, and advanced analytics showing collection diversity and completion percentages.
Our ultimate goal is to make professional-quality card grading accessible to every collector, anywhere in the world.
Built With
- firebase
- gemini
- genkit
- nestjs
- react
- typescript


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