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What is an ENS name?
An ENS name is a readable name on the Ethereum Name Service, such as alice.eth, that points to a crypto address. Wallets that support ENS can look up the address behind the name, so you can send to the name instead of a long string.
What it means for you
A .eth name is registered for a period and can expire; after a grace period it can be bought by someone else, who could then point it to their own address. Check that the address a name resolves to is the one you expect before sending.
A common mistake: “An ENS name proves who owns the address it points to.”
In fact: A name's owner can point it at any address and change it later, and a lapsed name can be bought by someone else. The name says where it resolves now, not who controls that address.
How it works
ENS has a registry of smart contracts recording who owns each name, and resolver contracts holding its records. A wallet converts the name with namehash, asks the registry which resolver the name uses, then reads the address record, which can include addresses on other chains. Separately, reverse resolution lets an address set a primary name, so wallets can show a name for an address. A .eth name is registered with a commit-reveal step, is an ERC-721 token, and 90 days after expiry goes into a 21-day auction whose price falls over time.
Sources: ENS docs: The protocol, ENS docs: ETH registrar · checked 4 October 2026
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Educational content, not financial advice. Written by hand and checked against the source named above. Something wrong? Tell us and we reply within two business days.