Shared Secret Key with ECDH

index.js

const secp256k1 = require("secp256k1");

const shared1 = secp256k1.ecdh(
    // Bob's public key
    Uint8Array.from(
        Buffer.from(
            "0458f41cfe6cbf9d9cbea548debfec39d5c4a16e6728bc8b251560cc7fbc36b92c79627fd0147444d7bf5f421755f5d3e2b15b3982a735ab86edb40840065cbb1d",
            "hex"
        )
    ),
    // Alice's private key
    Uint8Array.from(
        Buffer.from(
            "45fa0a3ec999835f9a39a6913297823af60ba064412653d63df8dfd9e89445aa",
            "hex"
        )
    )
);

const shared2 = secp256k1.ecdh(
    // Alice's public key
    Uint8Array.from(
        Buffer.from(
            "04525a4462fafd7f081b93b560e4ac2f3670952d3a81136c28bcb111362180b4f90bf000c71a04bd2874f5196c7bd81d468cfbbcf10cd9e895b74d06aab599b08b",
            "hex"
        )
    ),
    // Bob's private key
    Uint8Array.from(
        Buffer.from(
            "12dfdbb27aa0eb2b14e8e6daa29b359b02e9e376bd7064ea8f6765e331e63cfd",
            "hex"
        )
    )
);

console.log("Alice Shared Secret:", toHexString(shared1));
console.log("Bob Shared Secret:", toHexString(shared2));

// Helper method
function toHexString(byteArray) {
	return Array.prototype.map.call(byteArray, function (byte) {
		return ('0' + (byte & 0xFF).toString(16)).slice(-2);
	}).join('');
}