NFT domains are blockchain names, such as ENS .eth names, that their owners hold and trade as tokens. This guide explains how these names work, including expiry, renewal fees, ownership roles and the ENSv2 upgrade. It then lists the checks and features an NFT domain marketplace needs to stop buyers from paying for names that are about to expire or that the seller still controls.
Two kinds of NFT domains
- Web3-native names. ENS on Ethereum is the largest example, where a name such as
alice.ethpoints to a wallet address, a content hash or other records. Other name services exist on Solana and other chains. - Tokenized DNS domains. A tokenized DNS domain is an ordinary internet domain, such as
example.com, that a registrar represents on-chain, so transferring the token transfers control of the domain. Unstoppable Domains, for example, is now an ICANN-accredited registrar and offers "onchain" versions of DNS domains. A tokenized DNS domain still follows ICANN rules, and the registrar remains a trusted party.
ENS is the most widely used name service on Ethereum, so the rest of this guide focuses on ENS.
How ENS names work
Registration and pricing
ENS splits the .eth registrar into two contracts. The BaseRegistrar records who owns each name, and the controller handles registration and renewal. Registration uses a commit-reveal process, so nobody can see a pending registration and register the name first. Names must have at least three characters, and the ENS documentation lists these yearly prices:
| Name length | Price per year (USD, paid in ETH) |
|---|---|
| 5 or more characters | $5 |
| 4 characters | $160 |
| 3 characters | $640 |
Registration fees go to the ENS DAO treasury.
Expiry, grace period and premium
An ENS name lasts for the period the owner paid for. In ENSv1, an expired name enters a 90-day grace period, and only the previous owner can renew it during that time. After the grace period, a 21-day Dutch auction starts, during which a premium that starts near $100 million and falls toward zero is added to the normal price. After the auction, the name costs the normal price. A name that expires during a sale can leave the buyer with nothing.
Owner and manager
An unwrapped .eth name is an ERC-721 token in the BaseRegistrar, and the holder of that token is the owner. The ENS registry also records a manager, who can change where the name points. Transferring the token does not change the manager, so after a purchase the buyer must reclaim the manager role, and until then the seller can still change the name's records.
Wrapped names and subnames
The ENS Name Wrapper turns a name into an ERC-1155 token and adds "fuses." Burning a fuse removes a permission permanently, such as the right to create subnames or the right to transfer the name, and some wrapped names can no longer be transferred at all. Owners can also issue subnames such as pay.alice.eth, which projects use as community identities. In some setups, the owner of the parent name can take a subname back.
ENSv2 changes
ENS has deployed ENSv2 on the Sepolia testnet, and its documentation describes several changes that affect marketplaces:
- Names become ERC1155Singleton tokens, each with exactly one owner, as with ERC-721.
- The grace period falls from 90 days to 28 days, and anyone can renew a name during that period.
- Role-based permissions replace the Name Wrapper's fuses.
- A name's token ID changes when roles are granted or revoked, which cancels existing marketplace approvals. If a seller removes a permission before a purchase settles, the purchase fails, and the buyer does not receive a name with fewer rights.
- After ENSv2 goes live, new registrations happen on ENSv2, and owners move ENSv1 names to ENSv2 through migration contracts. Names that are not moved keep resolving through ENSv1.
A marketplace that launches now must index both versions and handle token IDs that change.
Features of an NFT domain marketplace
| Feature | Purpose |
|---|---|
| Expiry and renewal display | Shows buyers how long the name lasts and what renewal costs |
| Manager, fuse and role checks | Confirms the buyer will get full control of the name |
| Search by pattern | Finds names by length, digits only, emoji, dictionary words or palindromes |
| Category tags | Groups names into "clubs" such as all 3-digit or 4-letter names |
| Registration of available names | Lets users register free names directly, not only buy from other owners |
| Bulk renewal | Lets owners of many names renew them in one transaction |
| Look-alike warnings | Flags names that use Unicode characters resembling Latin letters |
Show the expiry date next to the price, warn on names that expire soon, and refuse listings for names already in the grace period.
Pricing and valuation of names
Name prices depend on a few properties: length, patterns such as repeated digits, dictionary words and potential brand use. Collectors group names into clubs, such as all three-digit names, and each club has its own floor price. A marketplace can offer clubs as filters and show recent sales of similar names.
The renewal fee also affects value, since a three-character name costs $640 a year to keep and a five-character name costs $5. Show the yearly renewal cost next to the asking price.
Build notes
- Use an existing order protocol such as Seaport for listings and offers, and before showing an order, check the name's expiry and its manager or roles.
- Index events from the ENS registry, the BaseRegistrar and the Name Wrapper, plus resolver records, and add the ENSv2 registries as they reach mainnet.
- Normalize every name with the ENSIP-15 rules, and flag confusable characters before listing.
- For tokenized DNS domains, integrate the issuing registrar's API and tell buyers which parts of the domain depend on the registrar.
The NFT marketplace development guide covers the general build, the OpenSea guide covers an open marketplace, and the Web3 wallet guide covers name display in wallets.
Frequently asked questions
What are NFT domains?
NFT domains are names, such as alice.eth, that exist as tokens on a blockchain. The owner can point the name at a wallet address or a website and can sell the name like any other NFT.
Do I own an ENS name forever?
No. You hold the name while the registration lasts and you keep renewing it. If the name expires and the grace period passes, anyone can register it.
Why does my purchased name still point to the seller's address?
Transferring the token changes the owner, but not the manager or the resolver records, so reclaim the manager role and update the records after the purchase.
Can .com domains be traded as NFTs?
Some registrars represent ICANN domains on-chain, so the token controls the domain, but the domain still follows ICANN rules and the registrar's terms.
Are look-alike names a risk?
Yes. Unicode characters that resemble Latin letters can make a fake name look identical to a real one. Normalize names and warn buyers about confusable characters.