IOST Unveils Official IRC-721 NFT Standard

IOST Foundation
Published in
6 min readApr 12, 2020


IOST officially releases its NFT Standard IRC-721. What are NFT? What does IRC-721 entail? What significance does it bring to the IOST ecosystem?

What are NFT?

With the launch of the Crypto kitties game in 2017, a new form of blockchain digital asset- Fungible Tokens NFT emerged.

If you’ve ever owned a cat, you’ll know that they are unique and not easy to replace. CryptoKitties replicated this concept in the crypto world — with each cat’s digital genetic material being stored on the blockchain

The common tokens that we see, such as IOST, are all fungible. There is no difference between each IOST (just like two 100 USD notes), which can be interchanged and divided. NFT are the opposite. Its important features are as follows:

  • each NFT has a unique token ID
  • NFT are not mutually interchangeable
  • the minimum unit is 1 and is indivisible (0.5 IOST exists, but in NFT, there only can be 1 NFT, for example, 0.5 crypto kitty does not exist)

NFT assets are the value medium used to characterize non-monetary assets. Thanks to the decentralization, immutability, and cryptographic confirmation of the blockchain, NFT solves a series of real problems of the real-world assets with the following characteristics:

  1. Better liquidity → can be traded efficiently and atomically;
  2. Cryptography confirmation → prevention of forging assets.

In addition, NFT has also achieved features that cryptocurrencies lack, such as characterizing negative assets (liabilities), identity, proof of equity, and virtual prop items. NFT fills the gap in crypto assets, allowing us to include assets with independent value into the scope of the crypto economy and obtain the protection of the blockchain.

IOST has begun to fully lay out the NFT market & now unveil the official IOST IRC-721 NFT standard to you.

IOST Official NFT Standard

The official IOST NFT standard protocol:

  • can be directly used by developers (for the basis for issuance), which lower the threshold & difficulty for developers to issue NFT assets
  • makes the NFT standard based on the IOST public chain unified, hence providing convenience for the NFT assets circulation (uniform issuance and circulation standards)
  • makes the reuse of NFT assets on different platforms or games on the IOST chain possible.

For users, the use of IOST NFT assets can promote the “NFTlization” of digital assets such as game assets, realize the confirmation of digital assets, solve the security problems of digital assets, and greatly improve the circulation of digital assets in the IOST ecosystem.

IRC-721 defines the NFT standard in the IOST ecosystem with the following technical features:

  • The main feature of IRC-721 is “Non-Fungible Token” (NFT). Each IRC-721 token has a unique token ID, and there will be only one owner;
  • A standardized process for seamless cross-chain transfer of assets will be applied
  • According to IRC721 specs, NFT can store token ID as well as metadata in its contract. When the metadata size is too big which is not cost-effective, developers can store the external URL of metadata and links to the metadata in the contract.
  • A locked transfer mechanism for digital assets/collections has been formulated to provide the flexibility in NFT assets issuance
  • A blacklist management function is available to meet the management needs for games and entertainment applications;

With IRC-721 standard, IOST envisions it to be the leader in the new generation of NFT asset standards.

NFT- IOST Tapping On New Blockchain Applications

Two major currency-free application areas of blockchain technology are consortium chains and NFT.

With consortium chains, IOST builds a one-stop BaaS platform to help developers or enterprises build chains quickly and provide enterprises with professional and targeted blockchain solutions.

The official IOST NFT standard is another strategic layout for IOST to implement blockchain technology.

Taking the field of online games where NFT is the most widely used as an example. Game props contain all relevant assets owned by players in the game. These assets have a common feature: players must acquire them either through playing the game and earn it or purchase with money.

Game props are a data form that is very suitable for characterization using NFT:

  • game props are produced and used on-chain, value support is provided by the game
  • most of the game equipment and characters are unique and can circulate freely, which matches the characteristics of NFT
  • NFT’s game props can also be used for cross-scenario, cross-server, and even cross-game property and reuse, making game assets no longer limited to an isolated scenario, but may become a truly universal currency within the ecosystem.

The official IOST NFT standard will be the basis for the IOST blockchain game field to attain the game assets rights and the free & efficient circulation among players. IOST aims to link the blockchain games and game assets in the IOST ecosystem through the NFT standard, open up the data isolation between blockchain games, and realize the mapping and reuse of NFT assets among multiple independent games.

In addition to games, the development of NFT will pave the way for IOST in new directions & opportunities: Collectibles, notes, registered securities, identity information, visas, property rights certificates, business agreements, membership cards, etc. are all potential application scenarios for NFT. NFT can be used where specific information needs to be recorded or personalized, to ensure that personal information cannot be tampered with or stolen so that the ownership of digital assets is clear.

In the future, IOST will fully deploy the NFT ecosystem and encourage the “NFTization” of digital assets such as game assets within the IOST ecosystem, which will bring new and fresh ideas for the implementation of IOST blockchain technology. At the same time, we also hope that more blockchain games can access the IOST official NFT standard, create a high-circulation and high-value IOST blockchain gaming ecosystem, and realize the cross-game reuse of game assets.

If you are interested in the IOST official NFT standard, you can consult the IRC-721 documents in:

IOST’s official wallet- Jetstream Chrome Extension currently supports IRC-721 tokens.

Finally, we would like to express our gratitude to XPET, a partner node of IOST, for this contribution to the development process of the IRC721 protocol & Jetstream developer for your help in this article.

Join The IOST Community!

With a mainnet that is one-year-old, IOST has swiftly risen to become a world-leading public chain renowned for its numerous government collaborations and enterprise partnerships around the world.

IOST’s Node Program is widely praised as one of the best staking programs globally by blockchain research institutions for its attractive returns, low risk and ease of use. To learn more and participate, please visit:

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