How can I get the owner wallet of an NFT mint using web3.js?

Question

Given a mint key of an NFT, how can I get the PublicKey of the wallet that owns it?

Answer 1

Since NFTs can only have 1 owner at a time, just use getTokenLargestAccounts to find the one that holds it

const connection = new Connection("https://api.mainnet-beta.solana.com");
const mintKey = new PublicKey("FfWP2mXizKnHZLsG3mTDFC2vWoZFfZTQi1Rpvm2nQTgM");
const largestAccounts = await connection.getTokenLargestAccounts(mintKey)
const largestAccountInfo = await connection.getParsedAccountInfo(
    largestAccounts.value[0].address  //first element is the largest account, assumed with 1 
);
console.log((largestAccountInfo.value.data as web3.ParsedAccountData).parsed.info.owner);

Answer 2

I have not benchmarked this one and the above answer, however I expect this one is a tad better on performance. It only requires one call on the chain.

public async getNftOwner(mintAddress: string) {
    let owner: string;
    try {
      // Fetch and parse all the accounts owned by the specified program id
      const accountInfo = await this.privateConnection.getParsedProgramAccounts(
        TOKEN_PROGRAM_ID,
        {
          filters: [
            { dataSize: 165 },
            { memcmp: { offset: 0, bytes: mintAddress } },
          ],
        },
      );
      // Get the account that has an amount of 1
      const tokenAccount = accountInfo.find((element) => {
        const data: { parsed: { info: { tokenAmount: { amount: string } } } } =
          element.account.data as {
            parsed: { info: { tokenAmount: { amount: string } } };
          };
        return data.parsed.info.tokenAmount.amount !== '0';
      });
      // Parsed data for the token account
      const data: { parsed: { info: { owner: string } } } = tokenAccount.account
        .data as {
        parsed: { info: { owner: string } };
      };
      // Set the owner
      owner = data.parsed.info.owner;
    } catch (error) {
      throw new HttpException(
        'Could not get wallet info from solana.',
        HttpStatus.SERVICE_UNAVAILABLE,
      );
    }
    return owner;
  }