# NFT metadata: where the name, image and attributes live

NFT metadata describes a token, often through a URI returned by an optional metadata interface. The token’s ownership record and the referenced name, attributes or media are different things. Owning an NFT does not by itself guarantee that external content remains available, unchanged or accompanied by copyright ownership.

Evidence: [Non-Fungible Token Standard](https://eips.ethereum.org/EIPS/eip-721)

Canonical: https://degreesofsatoshi.com/encyclopedia/nft-metadata/
Published: 2026-10-02
Substantively modified: 2026-10-02
Independently verified by an automated reviewer: 2026-10-02T18:12:41.505Z
Data current through: 2026-10-02

AI-assisted research and drafting with a separate automated source-verification pass; no external expert or named human review is implied.

## Key facts

- **Optional interface:** ERC-721 defines an optional metadata extension with name, symbol and tokenURI. ([Non-Fungible Token Standard](https://eips.ethereum.org/EIPS/eip-721))
- **Reference:** tokenURI can point to a JSON resource describing the token. ([Non-Fungible Token Standard](https://eips.ethereum.org/EIPS/eip-721))
- **Separation:** The token identifier and owner are distinct from the metadata resource. ([Non-Fungible Token Standard](https://eips.ethereum.org/EIPS/eip-721))

## Follow the reference chain

A collection contract identifies a token and its owner. A metadata URI can lead to a JSON document, whose image field can lead to another resource. Each step can have different storage and availability properties.

A media preview in a wallet is the result of resolving those references. It is not necessarily the image bytes stored in the token contract.

Evidence: [Non-Fungible Token Standard](https://eips.ethereum.org/EIPS/eip-721)

## Determine who can alter what is displayed

An implementation can construct or update metadata references under its own rules. A hosting operator may control a referenced server, while an upgrade authority may control future contract logic.

Check whether the URI and underlying content are fixed, content-addressed or administratively mutable. A unique token ID alone does not answer these questions.

Evidence: [Non-Fungible Token Standard](https://eips.ethereum.org/EIPS/eip-721); [Proxy contracts](https://docs.openzeppelin.com/contracts/5.x/api/proxy)

## Ownership of the token has a limited technical meaning

The ERC-721 interface defines token ownership and transfer behavior. It does not itself convey a universal license to reproduce the associated artwork or create a legal ownership registry.

Any content license or other rights need separate evidence from the relevant issuer or rights holder. Read those terms independently from the on-chain owner field.

Evidence: [Non-Fungible Token Standard](https://eips.ethereum.org/EIPS/eip-721)

## Questions

### If an NFT is on-chain, must its image also be on-chain?

No. The token can have an on-chain ownership record while its metadata or media is referenced elsewhere. Inspect the actual URI and storage arrangement.

Evidence: [Non-Fungible Token Standard](https://eips.ethereum.org/EIPS/eip-721)

## Claims and scope

### nft-metadata-quick-answer

NFT metadata describes a token, often through a URI returned by an optional metadata interface. The token’s ownership record and the referenced name, attributes or media are different things. Owning an NFT does not by itself guarantee that external content remains available, unchanged or accompanied by copyright ownership.

Scope: {"collection":"ethereum","dataAsOf":"2026-10-02","blockHeight":null}

### nft-metadata-fact-optional-interface

Optional interface: ERC-721 defines an optional metadata extension with name, symbol and tokenURI.

Scope: {"collection":"ethereum","dataAsOf":"2026-10-02","blockHeight":null}

### nft-metadata-fact-reference

Reference: tokenURI can point to a JSON resource describing the token.

Scope: {"collection":"ethereum","dataAsOf":"2026-10-02","blockHeight":null}

### nft-metadata-fact-separation

Separation: The token identifier and owner are distinct from the metadata resource.

Scope: {"collection":"ethereum","dataAsOf":"2026-10-02","blockHeight":null}

## Sources

- [Non-Fungible Token Standard](https://eips.ethereum.org/EIPS/eip-721) — Ethereum Improvement Proposals. Optional token metadata interfaces and the distinction between token and external resource. Locator: Specification: ERC721Metadata; Metadata Choices (metadata extension); NFT Identifiers. Retrieved: 2026-10-02T17:03:42.309Z.
- [Proxy contracts](https://docs.openzeppelin.com/contracts/5.x/api/proxy) — OpenZeppelin. Proxy implementation slots, delegated execution and upgrade authority. Locator: TransparentUpgradeableProxy; UUPSUpgradeable; ERC1967Proxy. Retrieved: 2026-10-02T17:03:43.024Z.

## Revision history

- 2026-10-02: First publication after primary-source research and independent automated verification.

## Cite this entry

Degrees of Satoshi editorial project. “NFT metadata: where the name, image and attributes live.” Published 2026-10-02; updated 2026-10-02. https://degreesofsatoshi.com/encyclopedia/nft-metadata/