🎨 Metaplex (NFTs)

Metaplex is the de facto standard and toolkit for NFTs on Solana: metadata (name, description, image), collections, and royalty enforcement. The Metaplex Token Metadata Program defines the on-chain layout and instructions.

🎯 Why Metaplex

Ecosystem standard — Magic Eden , Tensor , and most Solana NFT apps use Metaplex metadata
Metadata accounts — Store URI (pointing to JSON), name, symbol, creators, royalties
Collections — Group NFTs under a verified collection
SDKs — JS SDK and Umi for creating and reading NFTs

📚 Core Concepts

Concept	Description
Mint	SPL Token mint account; the NFT is a token with supply 1 and decimals 0
Metadata account	PDA (Program Derived Address) owned by the Metaplex program; holds URI, name, symbol, creators, etc.
Master Edition	For limited prints or verification; used by the Metaplex program
JSON off-chain	URI in metadata points to JSON with `name`, `description`, `image`, `attributes` (e.g. on IPFS or Arweave)

📝 Metadata JSON (Off-Chain)

Your tokenURI should resolve to JSON like:


{
  "name": "My NFT",
  "symbol": "MNFT",
  "description": "Description here",
  "image": "https://arweave.net/...",
  "attributes": [
    { "trait_type": "Background", "value": "Blue" }
  ],
  "properties": {
    "files": [{ "uri": "https://...", "type": "image/png" }],
    "category": "image"
  }
}

Host on IPFS, Arweave , or a CDN. See Metaplex standard .

📝 Creating an NFT (Metaplex JS)

Using @metaplex-foundation/mpl-token-metadata and the JS SDK:


import { createUmi } from "@metaplex-foundation/umi-bundle-defaults";
import { createMetadataAccountV3 } from "@metaplex-foundation/mpl-token-metadata";
import { createSignerFromKeypair, signerIdentity } from "@metaplex-foundation/umi";
import { Keypair } from "@solana/web3.js";
 
const umi = createUmi("https://api.devnet.solana.com");
const keypair = Keypair.fromSecretKey(/* ... */);
const signer = createSignerFromKeypair(umi, keypair);
umi.use(signerIdentity(signer));
 
// After creating the mint and token account (e.g. with @solana/spl-token)...
const metadata = {
  name: "My NFT",
  symbol: "MNFT",
  uri: "https://arweave.net/your-metadata-json",
  sellerFeeBasisPoints: 500, // 5%
  creators: null,
  collection: null,
  uses: null,
};
 
await createMetadataAccountV3(umi, {
  mint: mintKey,
  mintAuthority: signer,
  payer: signer,
  updateAuthority: signer.publicKey,
  data: {
    name: metadata.name,
    symbol: metadata.symbol,
    uri: metadata.uri,
    sellerFeeBasisPoints: metadata.sellerFeeBasisPoints,
    creators: metadata.creators,
    collection: metadata.collection,
    uses: metadata.uses,
  },
  isMutable: true,
  collectionDetails: null,
}).sendAndConfirm(umi);

📝 Reading NFT Metadata


import { createUmi } from "@metaplex-foundation/umi-bundle-defaults";
import { fetchMetadata } from "@metaplex-foundation/mpl-token-metadata";
import { publicKey } from "@metaplex-foundation/umi";
 
const umi = createUmi("https://api.devnet.solana.com");
const mint = publicKey("MintPubkey...");
 
const metadata = await fetchMetadata(umi, mint);
console.log(metadata.name, metadata.uri);
 
// Fetch JSON from URI
const json = await fetch(metadata.uri).then((r) => r.json());
console.log(json.image, json.attributes);