Blockchain-Based Certification for Online Quiz Competitions

Online quiz competitions have grown rapidly as tools for education, recruitment, and outreach. However, the integrity and provenance of certificates issued to winners and participants remain a concern: centralized certificate systems are vulnerable to tampering, forgery, and single-point failures. This paper presents a blockchain-based certification framework for online quiz competitions that ensures tamper-evident, verifiable, and easily-shareable digital certificates. We describe the system architecture, smart contract design, certificate generation workflow, and an implementation prototype using Ethereum-compatible smart contracts and InterPlanetary File System (IPFS) for off-chain storage of certificate metadata. Evaluation includes security analysis, gas-cost benchmarking, and a user verification latency study. Results show that the proposed approach provides strong integrity guarantees, acceptable cost for small-to-medium events, and fast verification (sub-second for on-chain lookups when using light clients). We conclude with limitations, potential improvements, and directions for future work.