How to Verify a Keypair

If you are given a keypair, you can verify whether or not the secret matches the given public key

verify-keypair.ts
import { Keypair, PublicKey } from "@solana/web3.js";
 
const publicKey = new PublicKey("24PNhTaNtomHhoy3fTRaMhAFCRj4uHqhZEEoWrKDbR5p");
 
const keypair = Keypair.fromSecretKey(
  Uint8Array.from([
    174, 47, 154, 16, 202, 193, 206, 113, 199, 190, 53, 133, 169, 175, 31, 56,
    222, 53, 138, 189, 224, 216, 117, 173, 10, 149, 53, 45, 73, 251, 237, 246,
    15, 185, 186, 82, 177, 240, 148, 69, 241, 227, 167, 80, 141, 89, 240, 121,
    121, 35, 172, 247, 68, 251, 226, 218, 48, 63, 176, 109, 168, 89, 238, 135,
  ]),
);
 
console.log(keypair.publicKey.toBase58() === publicKey.toBase58());
// output: true