Reveal

A reveal is not an EIP or a formal standard but an operational NFT launch pattern, also called delayed reveal or pre-reveal. Its logic is simple: until the unveiling, every token shows a placeholder image and metadata, and only afterward are these swapped for the final ones. The whole mechanic lives in how the tokenURI() and baseURI() functions resolve metadata.

In practice, the contract initially points baseURI at generic metadata while a state flag marks the collection as unrevealed, so tokenURI(tokenId) returns the placeholder. At the reveal, the team updates baseURI or decrypts an encrypted URI to point at the real metadata, and tokenURI begins returning the final image and attributes. A common good practice is to publish a provenance hash before the mint, a cryptographic fingerprint of the full set of artwork and its order, which later proves the collection was not altered once the sale began.

The reveal and the allowlist are complementary launch phases. The allowlist governs who can mint and when; the reveal governs when the final art is seen. Used together, they reduce the bias of hunting for rare traits during the mint. thirdweb offers the best-documented implementation, with ERC721DelayedReveal and ERC1155DelayedReveal base contracts and a DelayedReveal extension that combines an encrypted URI and a provenance hash.