TRC-721: the NFT standard behind tokenized art on TRON

APENFT Asia editorial team · Fact-checked against official sources

What TRC-721 is, in plain English

TRC-721 is the token standard TRON uses for non-fungible tokens, the “NFT” in the everyday sense of a unique digital collectible. Its formal name is TIP-721, short for TRON Improvement Proposal 721. The proposal was created in November 2020, carries the status Final in the official TRON TIPs repository, and was deliberately written to be compatible with Ethereum’s EIP-721. Anyone who has worked with ERC-721 on Ethereum will find the same functions and events on TRON.

The idea is simple. A fungible token like TRX or USDT works like cash: one unit is worth exactly the same as any other unit, and you can split it into fractions. A non-fungible token works more like a deed or a numbered ticket. Each token has its own token ID inside its contract, exactly one address owns it at any moment, and it cannot be divided. If you own token #42 in a collection, nobody else owns #42, and it is not interchangeable with #43.

That property is what made TRC-721 the natural home for tokenized art on TRON. When the APENFT Foundation set out to “register world-class artworks as NFTs on the blockchain”, as its white paper puts it, each artwork needed its own one-off token. A fungible coin could not do that job.

TRC-721 vs the APENFT coin: a common mix-up

The name causes confusion. APENFT (now rebranded as AINFT) has a token whose ticker is literally NFT, yet that token is not a non-fungible token. It is an ordinary TRC-20 token: fungible, divisible down to six decimal places, with a maximum supply of 999.99 trillion units at contract TFczxzPhnThNSqr5by8tvxsdCFRRz6cPNq. You can read the full supply breakdown in our APENFT tokenomics guide.

The artworks are a separate layer. The white paper lists, for example, Picasso’s Femme nue couchée au collier as tokenized on a TRON TRC-721 contract, TCzUYnFSwtH2bJkynGB46tWxWjdTQqL1SG. So the project uses both standards side by side: TRC-20 for the coin people trade on exchanges, and TRC-721 for the one-of-a-kind art records.

Formal name

TIP-721 (TRC-721)

Status

Final

Created

November 2020

Compatible with

Ethereum EIP-721 (ERC-721)

Token type

Non-fungible, indivisible, one owner per ID

APENFT coin standard

TRC-20, 6 decimals (not TRC-721)

Example art contract

TCzUYnFSwtH2bJkynGB46tWxWjdTQqL1SG (Picasso NFT)

Wallet support

TronLink: TRC-20 and TRC-721

How TRC-721 works under the hood

Because TIP-721 mirrors EIP-721, the core interface is the familiar one. A compliant contract exposes a handful of functions that every wallet, explorer and marketplace knows how to call:

• balanceOf(owner) returns how many tokens from this contract an address holds.
• ownerOf(tokenId) returns the single address that owns a given token.
• transferFrom and safeTransferFrom move a token from one owner to another. The “safe” version checks that a receiving contract can actually handle NFTs, so tokens do not get stuck.
• approve lets one other address move a single token on your behalf. setApprovalForAll gives an operator, usually a marketplace contract, permission over every token you hold in that collection.
• A Transfer event is emitted on every move, which is how explorers such as Tronscan build an ownership history.

On top of that core, the optional metadata extension adds a collection name, a symbol and, most importantly, tokenURI(tokenId). That function returns a link to a small JSON file describing the token: title, description, attributes and the address of the image or video. There is also an optional enumeration extension that lets apps list every token in a contract.

The metadata problem

Here is the part many buyers miss. The blockchain stores the token ID and the owner. It usually does not store the artwork. Storing a high-resolution image directly on any public chain would be extremely expensive, so the token points to a file somewhere else. Where that “somewhere else” is decides how durable your NFT really is.

APENFT chose the BitTorrent File System (BTFS) for artwork data, according to its white paper. BTFS is a decentralized storage network, which in principle is sturdier than a single company’s web server. It is worth knowing, though, that btfs.io now redirects to a different project name, bttinfergrid.ai. That does not mean files are lost, but it shows why collectors should check where metadata resolves today, not only where it resolved at mint.

Royalties are not part of the standard

TIP-721, like EIP-721, defines ownership and transfers. It does not define a royalty. When a marketplace pays the original artist a percentage on resales, that comes from marketplace rules or from extra code in that specific contract. If the royalty matters to you as an artist or as a buyer, read the platform’s terms rather than assuming the standard enforces it.

TRC-20 vs TRC-721 vs TRC-1155 vs ERC-721

TRON has several token standards, and Ethereum’s ERC-721 is the reference that TRC-721 copies. The table puts them side by side.

TRC-1155 (TIP-1155, the “Multi Token Standard”) reached Final status in July 2022. A single TRC-1155 contract can hold many token types at once: some fungible, such as 10,000 copies of a game potion, and some unique, such as one legendary sword. It suits games and limited editions, where deploying a separate TRC-721 contract per item would be wasteful. For a one-off painting, TRC-721 is still the cleaner fit.

TRC-404 is not a finalized TIP in the same sense. It is a hybrid idea that tries to make an NFT partly fungible, so it can trade on a bonding curve like a token. The white paper describes NFT Pump, launched in September 2024, as a launchpad using TRC-404 with “pump”-style pricing. Treat it as experimental and speculative.

ERC-721 is the Ethereum original. TRC-721 keeps the same interface, so tools and contract logic port across with small changes. The practical differences are the network: TRON addresses start with T, and you pay fees in Energy and Bandwidth rather than ETH gas. That makes simple actions on TRON cheap in absolute terms, though “cheap” depends on whether you hold resources. Our TRON energy calculator shows how those fees are worked out.

How a work of art becomes a TRC-721 token

Tokenizing art is less magical than the marketing suggests. For a physical painting, the token is a digital certificate that points to an image and a description of the work. For a born-digital piece, the token points to the file itself. Here is the typical flow on TRON.

We have not measured the exact Energy cost of a TRC-721 mint or transfer, and it varies with how each contract is written. As a reference point, a plain transfer of the NFT TRC-20 coin measured about 14,309 Energy to an address that already holds it, or about 29,309 Energy to a new holder. At a price of 100 sun per Energy unit, that is roughly 1.43 or 2.93 TRX if burned. These network parameters are set by TRON governance and can change.

Where TRC-721 is used in the APENFT world

The APENFT Marketplace, now called AINFT Market at marketplace.ainft.com, launched on mainnet on 15 April 2022 and was billed as the first official NFT marketplace on TRON. It is TRON-native and built around TRC-721, with Ethereum and BNB Chain support reported by secondary sources. At launch it advertised zero initial transaction fees, and the white paper mentions a gas-fee subsidy of up to 90 percent. Activity today is very low: one February 2026 report put average volume at about six US dollars a day. Our AINFT marketplace review covers its current state honestly.

Beyond the official market, TRC-721 is the format of TRON collections such as TPunks, a 10,000-piece pixel-punk set. TPunk #3442 “Joker” was bought for 120 million TRX in August 2021 and donated to APENFT. Independent marketplaces such as Kraftly also trade TRC-721 collections. You can browse what is still active in our directory of TRON NFT projects.

For the art side, the white paper’s appendix lists the Foundation collection, from Picasso and Beeple to Pak’s cubes and Cattelan’s Comedian. We cover each piece, and the questions around them, in the guide to the APENFT art collection.

Strengths and weak points of TRC-721

What a TRC-721 token does and does not give you

This is the question that matters most if you are buying, not building. Owning a TRC-721 token proves that your address controls that token ID in that contract. It does not, by default, give you:

• Legal title to a physical object. If the token represents a painting in a vault, your rights depend on the issuer’s terms and on the law where the object is held. A token is a pointer, not a deed recognized by every court.
• Copyright. Unless the terms say so, the artist or rights holder keeps the copyright. You own the token, not the right to print merchandise.
• Guaranteed liquidity. A unique item only sells when a buyer wants that exact item. On a quiet market, that may never happen.

The Giacometti Le Nez case shows why this matters. In 2021, Justin Sun bought the sculpture and announced it as a donation to APENFT. In 2025, he and collector David Geffen ended up in court over who holds title, with claims and counterclaims that are still unresolved as far as we can verify. We take no side here. The lesson is general: announcements and tokens are not a substitute for clear legal paperwork.

How to check a TRC-721 token before you buy

1. Get the contract address from an official source. Use the project’s own site or white paper, not a link from a DM or a reply under a post.
2. Look it up on Tronscan. Check who deployed it, when, and how many tokens exist. Our TRON explorer tool lets you query an address directly.
3. Open the tokenURI. Make sure the metadata loads and the image is stored on durable storage, not a dead link.
4. Check the transfer history. A token that changed hands many times between a few related addresses may be wash-traded.
5. Read the approval you are signing. “Approve all” for a marketplace is normal; “approve all” for an unknown site is how wallets get drained.
6. Use a proper wallet. TronLink shows TRC-721 assets and lets you review approvals.

If you get these six checks right, you avoid most of the problems people run into with TRON NFTs. The standard itself is solid. The risks sit around it: storage, rights, liquidity and fake contracts. For a broader view on staying safe, read our guide on whether APENFT is safe.