Allowlist

An allowlist is a standard operational pattern of NFT launches, not an EIP or a numbered standard. It is the preferred term over the older whitelist, which much of the sector has stopped using; in practice they are used as synonyms, but the current form is allowlist or AL. Its purpose is to grant priority access to mint in an early presale phase, ahead of the public mint.

The usual on-chain implementation uses a Merkle tree. The team compiles the final list, generates the Merkle root and uploads it to the mint contract; when minting, each wallet supplies a Merkle proof that the contract verifies against the root, with no need to store thousands of addresses on-chain, which is cheap and gas-efficient. Mint stages enforce on-chain which sets of wallets can mint in each phase, typically lasting from a few hours to a day. An off-chain variant also exists, with signatures and lists managed off-chain and validated at mint time.

It is the default access-control pattern in launches: it rewards the early community, smooths demand and gives the drop predictability by filtering competition to a known list. It pairs with the reveal, minting with a placeholder during the allowlist phase and unveiling the art afterward. OpenSea documents and offers allowlists for drops, and Crossmint documents them with a Merkle tree for Ethereum and Polygon.