A DECENTRALIZED FRAMEWORK FOR ACADEMIC CERTIFICATE ISSUANCE, VERIFICATION, AND REVOCATION USING ETHEREUM SMART CONTRACTS AND IPFS: DESIGN, IMPLEMENTATION, AND EVALUATION ON THE SEPOLIA TESTNET

Academic certificate fraud is a persistent problem across developing economies, undermining trust between graduates, employers, and higher education institutions. In Nigeria, this has prompted a federal mandate requiring every employer to verify staff credentials; yet existing verification processes remain manual, slow, and easily circumvented. This paper proposed, implemented, and evaluated a fully decentralized academic certificate management framework built on the Ethereum blockchain, leveraging Solidity smart contracts, the InterPlanetary File System (IPFS) for off-chain document storage, QR-code-enabled instant verification, and on-chain revocation.The system was deployed and tested on the Ethereum Sepolia testnet using Hardhat 2.19.4 and ethers.js 6.x. Results show that issuing a single certificate costs a fraction of a cent, that batch issuance lowers this cost further, that verification is free for employers, and that the system correctly detects fabricated or altered certificates in the overwhelming majority of cases while cutting verification time from days to seconds. These findings demonstrate that blockchain-based credential management is technically sound, affordable, and readily deployable in resource-constrained institutional settings, offering a practical path toward restoring trust in academic credentials across Nigerian and other African universities.