🚀 CertiChain – Blockchain Certificate Verification System

A decentralized certificate verification platform built using React, Ethers.js, and Ethereum (Sepolia Testnet). CertiChain ensures tamper-proof, verifiable, and transparent certificate validation using blockchain technology.

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✨ Key Features

🔐 Blockchain Security

• Immutable certificate storage on Ethereum
• Smart contract-based verification
• Admin-controlled certificate issuance
• Tamper-proof digital records

⚙️ Core Functionality

• ✅ Add certificates (Admin only)
• ✅ Verify certificates using hash
• ✅ View all certificates on-chain
• ✅ QR-based certificate sharing
• ✅ Multi-network support (Ganache + Sepolia)

🎨 User Experience

• Modern glassmorphism UI
• Dark / Light mode support
• Responsive design (mobile-friendly)
• Real-time transaction feedback
• Wallet reconnect + network switch support

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🧱 Tech Stack

Layer	Technology
Frontend	React + Vite
Blockchain	Solidity (Ethereum)
Web3	Ethers.js v6
Styling	Tailwind CSS
Wallet	MetaMask
QR Code	qrcode.react

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📸 Screenshots

🔗 Wallet Connected (Sepolia)

Shows MetaMask connected with Sepolia testnet and active wallet session.

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🔍 Verify Certificate

Users can verify certificate authenticity using a unique hash stored on blockchain.

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➕ Add Certificate (Admin)

Admin panel for adding new certificates securely to the blockchain.

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📄 All Certificates

Displays all certificates stored on-chain with student and course details.

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🧾 MetaMask Activity

Blockchain transactions including contract deployment and certificate addition.

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⚡ Getting Started

1. Clone Repository

git clone https://github.com/your-username/certichain.git
cd certichain

2. Install Dependencies

npm install --legacy-peer-deps

3. Configure Smart Contract

Update contract address in:

src/utils/contract.js

const CONTRACT_ADDRESS = "YOUR_DEPLOYED_CONTRACT_ADDRESS";

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4. Run Project

npm run dev

Open:

http://localhost:3000

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🌐 Network Configuration

Supports:

• 🏠 Ganache (Local)
• 🌍 Sepolia (Testnet)

chainId: '0x539'      // Ganache
chainId: '0xaa36a7'   // Sepolia

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🧪 How It Works

🔹 Add Certificate (Admin)

1. Connect MetaMask
2. Fill certificate details
3. Approve transaction
4. Data stored on blockchain

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🔹 Verify Certificate

1. Enter certificate hash

2. Click verify

3. View:

   • Student Name
   • Course
   • Issue Date
   • QR Code

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🔹 View All Certificates

• Fetches all stored hashes
• Displays certificate list
• Click to verify details

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📦 Build & Deployment

npm run build
npm run preview

🚀 Recommended Deployment

• Vercel (Frontend)
• Sepolia (Smart Contract)

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🛡️ Security Notes

• No private keys stored in frontend
• All transactions require MetaMask approval
• Admin-only functions enforced via smart contract
• Always test on testnet before mainnet

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📌 Future Improvements

• NFT-based certificates
• IPFS document storage
• Certificate revocation system
• Advanced search & filtering
• Multi-admin roles

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👨‍💻 Author

Krishnik Barman 🔗 GitHub: https://github.com/krishnikbarman

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📜 License

MIT License