isApprovedForAlladdress

isApprovedForAll(address owner, address operator) is a function defined in the ERC-721 standard that allows an NFT owner to authorize a third party to manage all of their tokens. It is a public view function that returns a boolean value indicating whether the operator has blanket approval to handle every token owned by the specified owner.

How it works: an owner can grant or revoke blanket permission by calling setApprovalForAll(address operator, bool approved). If approved is true, the operator is empowered to transfer any of the owner’s NFTs; if false, that ability is withdrawn. The approval is recorded per owner-operator pair and applies to all of the owner’s NFT assets.

Relationship to other approvals: isApprovedForAll differs from per-token approvals granted by approve(address to, uint256 tokenId), which authorize a single operator for one specific token. isApprovedForAll covers all tokens owned by the owner, simplifying broad management by trusted entities such as marketplaces or custodians.

Common use cases: marketplaces, wallet providers, and other services that need to transfer or manage a user’s NFTs on behalf of the user typically rely on isApprovedForAll to determine permission status before performing transfers.

Security and best practices: blanket approvals increase risk if the operator is compromised or misused, since the operator can act on behalf of the owner for all tokens. Users should grant such permission only to trusted entities and revoke it promptly if trust is lost. In smart contract code, isApprovedForAll is typically checked before performing transferFrom on behalf of the owner.

See also: ERC-721, setApprovalForAll, approve.