In the Sui blockchain, an Object ID is a unique identifier assigned to every object stored on the chain. Objects are a core part of how Sui works—they can represent things like:

User-owned assets (NFTs, tokens, etc.)

Smart contract data

Packages (deployed code modules)

Any stateful data structure

🔍 Why is Object ID Important? Each time you interact with the Sui blockchain (e.g., mint an NFT, transfer tokens, call a smart contract), the resulting data—whether it's a new asset or a change in state—is stored as an object with its own Object ID. This ID allows:

Tracking ownership (since objects can be owned by accounts or other objects)

Referencing in transactions (smart contracts often require the Object ID as an input)

Auditing and querying the blockchain to retrieve specific on-chain data

🧱 Object ID Format A typical Object ID is a base-58-encoded string or a hexadecimal hash that looks like:

Copy Edit 0x5f1c4e9d8be8e2b2b7f1f1cd95742d9e8c6234423ea8b977d25e88c19b73dc9f This string is a fingerprint of the object, making it globally unique across the Sui blockchain.

🔁 Use in Transactions When submitting a transaction—like transferring a coin—you’ll usually need to provide the Object ID of the asset. For example, to transfer a specific SUI coin, you’d reference its object ID in your call.

🛠 How to Find an Object ID In a Sui Wallet: When you view assets or NFTs, each item has a clickable Object ID.

Blockchain Explorer: Tools like explorer.sui.io let you search for Object IDs to see history, owner, and metadata.

Developer CLI: If you're using the Sui CLI, commands like sui client objects or sui client query can list your wallet's objects and their IDs.

An Object ID in the context of a Sui transaction refers to a unique identifier assigned to an object on the Sui blockchain. It is a 32-byte globally unique ID that is derived from two components:

• The digest of the transaction that created the object : This ensures that the Object ID is tied to the specific transaction responsible for its creation.
• A counter encoding the number of IDs generated by the transaction : This helps differentiate between multiple objects created within the same transaction.

For example, when a new object (such as a token, NFT, or other digital asset) is created on Sui, the system generates an Object ID to uniquely identify it. This ID is crucial for referencing the object in subsequent transactions, such as transfers, mutations, or queries.

Additionally, every object in Sui has a version (an 8-byte unsigned integer) that increments with each modification, ensuring proper tracking of the object's state over time. The combination of the Object ID, version, and digest provides a robust mechanism for managing and interacting with objects on the Sui blockchain.

In practical terms, when using tools like the Sui TypeScript SDK, you can reference an object in a transaction by passing its Object ID using methods like tx.object. This makes Object IDs a foundational element for building and interacting with applications on Sui.

An Object ID in the context of a Sui transaction is a unique identifier for an object on the Sui blockchain. It is derived from two components: the digest of the transaction that created the object, and the counter that encodes the number of IDs generated by the transaction that increases monotonically with each transaction that modifies it, which helps track changes and updates to the object over time.

To reference an object within a transaction, you would typically use its Object ID, either directly or through a resolved object reference. This allows the transaction to interact with that specific object, such as using it as input, transferring it, or modifying it