The spread of fake goods poses serious problems for industries like luxury goods, electronics, fashion, and pharmaceuticals, leading to monetary losses, harm to brand reputation, and a decline in consumer confidence. Conventional authentication techniques, like QR codes, RFID tags, and centralized databases, are insufficient for effective counterfeit deterrence because they are susceptible to duplication, tampering, and security flaws. To address these issues, this paper suggests a blockchain-based authentication system that uses a decentralized, transparent, and impenetrable ledger to confirm the legitimacy of products. The proposed framework makes it simple to verify product information by using MetaMask for secure user interactions and Ganache to simulate a local blockchain network. By automating procedures like product registration, ownership tracking, and authentication, smart contracts make sure that data is indestructible and verifiable throughout the supply chain. Blockchain technology greatly increases transparency and cuts the risk of fraud through doing away with the need for centralized systems. By scanning a QR code connected to blockchain records, customers can instantly access the product's history and confirm the authenticity of the product. This strategy strengthens consumer confidence and improves supply chain security. To improve counterfeit prevention and authentication techniques even more, future advancements could involve AI-driven fraud detection, predictive analytics, and IoT-enabled real-time tracking.

Index Terms: Blockchain, Product Authentication, Smart Contracts, Fraud Prevention, MetaMask, Ganache, QR Code