🔗 BlockCert

Blockchain-Based Academic Credential Verification System

A decentralized application (DApp) that eliminates certificate fraud using cryptographic hashing and immutable smart contracts on Ethereum.

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🧩 The Problem

Academic credential fraud is rising globally. Traditional verification methods:

• 🐢 Take days or weeks to process
• 🏛️ Rely on centralized databases prone to tampering
• 👀 Require manual human checks
• 🔓 Are vulnerable to forgery

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✅ The Solution

BlockCert stores cryptographic proofs of certificates on-chain — not the files themselves — making forgery mathematically impossible. Institution uploads certificate ↓ SHA-256 hash generated (frontend) ↓ Hash stored via smart contract ↓ Immutable record on Ethereum

Anyone can verify a certificate by re-hashing the file and matching it against the on-chain record — instantly, trustlessly, globally.

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🛠️ Tech Stack

Layer	Technology
Smart Contract	Solidity v0.8.21
Dev Environment	Hardhat
Blockchain Interaction	Ethers.js
Wallet	MetaMask
Frontend	Next.js
Hashing	CryptoJS (SHA-256)

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📜 Smart Contract

Written in Solidity v0.8.21. Deployed on a local Hardhat network.

Core Functions

issueCertificate(studentId, hash)   // Institution issues a certificate
verifyCertificate(studentId, hash)  // Anyone verifies authenticity
revokeCertificate(studentId)        // Institution revokes a certificate
getCertificate(studentId)           // Fetch certificate record

Certificate Record Structure

Field	Description
hash	SHA-256 hash of the certificate file
timestamp	Time of issuance
isRevoked	Revocation status

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⚙️ How It Works

🎓 Issuance

1. Institution uploads a certificate file
2. Frontend generates a SHA-256 hash of the file
3. Hash is submitted to the smart contract
4. Transaction is recorded permanently on the Ethereum network

🔍 Verification

1. Verifier uploads the certificate file
2. File is hashed again using SHA-256
3. Hash is compared against the on-chain record
4. Returns ✅ Authentic or ❌ Invalid / Revoked

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🖥️ Screenshots

Issuance Flow	Verification Flow

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🚀 Setup & Run Locally

Prerequisites

• Node.js installed
• MetaMask browser extension
• MetaMask connected to Hardhat Local (Chain ID: 31337)

Steps

# 1. Install dependencies
npm install

# 2. Start Hardhat local node
npx hardhat node

# 3. Deploy the smart contract
npx hardhat run scripts/deploy.js --network localhost

# 4. Update contract address in the frontend config

# 5. Start the frontend
npm run dev

🌐 App runs at http://localhost:3000

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🔐 Security Design

Measure	Purpose
SHA-256 Hashing	Ensures certificate integrity
Immutable Smart Contract	Prevents unauthorized tampering
Revocation Mechanism	Invalidates compromised certificates
No file stored on-chain	Protects sensitive data

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🔮 Future Improvements

• Role-based access control (institutions only for issuance)
• Deployment to Sepolia testnet
• QR code based instant verification
• Institutional login & authentication
• IPFS integration for decentralized file storage

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💡 Why Blockchain?

Property	Benefit
Immutability	Records cannot be altered once stored
Transparency	Anyone can audit the chain
Cryptographic Trust	Math, not middlemen
Decentralization	No single point of failure or authority

BlockCert removes the need for centralized verification authorities entirely.