NFT On-Chain Royalties (EIP-2981) 3

Question 1

In OpenZeppelin's ERC2981 contract, what does _setDefaultRoyalty set?

Accepted Answer

A collection-wide royalty receiver and fee

Answer

_setDefaultRoyalty configures a default receiver and fee fraction applied to all tokens lacking a specific override.

Question 2

How does OpenZeppelin let you override royalties for one specific token?

Accepted Answer

_setTokenRoyalty

Answer

_setTokenRoyalty assigns a per-token receiver and fee that takes precedence over the default.

Question 3

In OpenZeppelin's implementation, what is the denominator for the fee fraction by default?

Accepted Answer

10000 (basis points)

Answer

The default _feeDenominator returns 10000, so fees are expressed in basis points (e.g., 500 = 5%).

Question 4

A fee numerator of 250 with the default denominator represents what royalty?

Accepted Answer

2.5%

Answer

250 / 10000 equals 0.025, which is a 2.5% royalty.

Question 5

What happens if you set a fee numerator greater than the denominator in OpenZeppelin's ERC2981?

Accepted Answer

The transaction reverts with a royalty-too-high error

Answer

OpenZeppelin reverts if the fee numerator exceeds the denominator, preventing royalties above 100%.

NFT Development Practice Test