NFT: How it works

Core concepts and processes behind Non‑Fungible Tokens (NFTs) in the TON Blockchain, aligned with TEP‑62.

Related smart contracts

Standardized NFTs on TON are implemented using a set of smart contracts, including:

• NFT collection smart contract
• NFT item smart contract

The NFT standard provides only a general interaction scheme, leaving specific implementation details to developers.

NFT collection

The collection is the source of truth for items. It should provide each NFT item’s address, its own collection metadata, and, given an index and individual item metadata, can provide full item metadata.

NFT item

Following TON’s contract sharding approach, each NFT item is its own smart contract account. It provides the collection address, index, current owner, and individual metadata. On a valid transfer from the current owner, it updates the owner, optionally notifies the new owner, and returns excess Toncoin to the specified address.

Transfer NFT item

The current owner sends a transfer message to the NFT item contract. The item updates its owner field and, optionally, sends a notification and/or excess Toncoin to the specified addresses.

Transfer message body contains the following data:

Field	Type	Description
transfer	uint32	tag equal to 0x5fcc3d14
query_id	uint64	arbitrary request number
new_owner	MsgAddress	address of the new owner of the NFT item
response_destination	MsgAddress	optional address to receive excess Toncoin, usually the sender’s address
custom_payload	Maybe ^Cell	optional custom data
forward_amount	VarUInteger 16	the amount of Toncoin to be sent to the new owner
forward_payload	Either Cell ^Cell	optional data that should be forwarded to the new owner

TL-B

transfer#5fcc3d14 query_id:uint64
                  new_owner:MsgAddress
                  response_destination:MsgAddress
                  custom_payload:(Maybe ^Cell)
                  forward_amount:(VarUInteger 16)
                  forward_payload:(Either Cell ^Cell)
                  = InternalMsgBody;

Ownership notification message body (ownership_assigned) contains the following data:

Field	Type	Description
ownership_assigned	uint32	tag equal to 0x05138d91
query_id	uint64	should be equal to request’s query_id
prev_owner	MsgAddress	address of the previous owner of this NFT item
forward_payload	Either Cell ^Cell	should be equal to request’s forward_payload

TL-B

ownership_assigned query_id:uint64
                   prev_owner:MsgAddress
                   forward_payload:(Either Cell ^Cell)
                   = InternalMsgBody;

Excess message body (excesses) contains the following data:

Field	Type	Description
excesses	uint32	tag equal to 0xd53276db
query_id	uint64	should be equal to request’s query_id

TL-B

excesses query_id:uint64 = InternalMsgBody;

The transfer must be rejected if:

1. The inbound message is not from the current owner.
2. There are not enough coins (considering storage fee guidelines) to process the operation and send forward_amount.

Get static data

Anyone can send a get_static_data message to an NFT item to request its static data (index and collection address). The item responds with report_static_data message using send mode 64 (return message amount except gas fees).

Get static data message body contains the following data:

Field	Type	Description
get_static_data	uint32	tag equal to 0x2fcb26a2
query_id	uint64	arbitrary request number

TL-B

get_static_data#2fcb26a2 query_id:uint64 = InternalMsgBody;

Report static data message body contains the following data:

Field	Type	Description
report_static_data	uint32	tag equal to 0x8b771735
query_id	uint64	should be equal to request’s query_id
index	uint256	numerical index of this NFT in the collection
collection	MsgAddress	address of the smart contract of the collection to which this NFT belongs

TL-B

report_static_data#8b771735 query_id:uint64 index:uint256 collection:MsgAddress = InternalMsgBody;

Best practices

• Metadata referenced by each link should be permanent. If you need to change it, send a transaction that updates the reference.
• Be mindful of TON’s asynchronous nature: on‑chain “current owner” reads may become stale by the time you act on them.