ENS Namehash Calculator

How to Use the ENS Namehash Calculator

The ENS namehash calculator lets you check the identifier for a chosen ENS name. Enter the full name in the ENS name field, for example vitalik.eth. The field defaults to vitalik.eth, and when the page loads, the result for that value appears immediately without any extra clicks.

• Enter the ENS name you want to check.
• Click the Calculate namehash button.
• Read the Namehash result for the full name.
• Read the First-label labelhash result for the leftmost part.

A namehash is written as 0x followed by 64 hex characters, or 32 bytes. The first-label labelhash also appears as 0x followed by 64 hex characters, or shows — for an empty name. Calculations run locally in your browser, so the name you enter is not sent to a server.

What Is Namehash and What Is It Used For in ENS

ENS is a naming system where names like vitalik.eth can point to addresses, data, or other resources. For different applications to recognize the same name in the same way, they need a repeatable identifier. That identifier is the namehash.

The namehash is computed according to the EIP-137 algorithm. For a full name, one result is produced that uniquely represents that name in ENS. This lets a wallet, app, or service look up the same name and get the same identifier, no matter how the name is stored in a given place — as long as it has gone through the required normalization.

Namehash is useful when working with ENS names, subdomains, and records. It does not replace checking whether a name exists, who controls it, or what records are set. It is a computational identifier, not proof of ownership.

In practice, namehash lets applications talk about the same name without confusion. If you know the namehash, you can use it in tools and documentation that work with ENS identifiers. For an empty name after trimming, the calculator shows the root namehash, which is 32 zero bytes, and the first-label labelhash as —.

EIP-137 Algorithm Step by Step

The calculator uses the EIP-137 algorithm. First, the name is trimmed and converted to lowercase. If it is not empty after trimming, it is split on dots into labels. Labels are processed from right to left, meaning from the end of the name toward the beginning.

1. Start: the initial result is 32 zero bytes, written as 0x000...000.
2. For each label, compute the Keccak-256 hash of its UTF-8 representation.
3. Concatenate the current result with the label hash, then hash the whole thing again with Keccak-256.
4. This produces a new result for each subsequent label until all labels are processed.
5. After the full name is processed, you get the namehash.

Example for the default value vitalik.eth: the name splits into the labels vitalik and eth. The eth label is processed first, then vitalik. When the calculation finishes, the namehash is 0xee6c4522aab0003e8d14cd40a6af439055fd2577951148c14b6cea9a53475835. The first-label labelhash, for the vitalik label, is 0xaf2caa1c2ca1d027f1ac823b529d0a67cd144264b2789fa2ea4d63a67c7103cc.

The tool shows both results as hex strings. Namehash covers the full name, while the first-label labelhash covers only the leftmost part. The result appears immediately for the default value, and for your own name you just need to click the Calculate namehash button.

Namehash vs. Labelhash — Differences and Uses

Namehash and labelhash sound similar but describe different things. Namehash is the identifier for a full ENS name, such as vitalik.eth. Labelhash is the identifier for a single label, meaning one segment of a name separated by a dot.

In the calculator, labelhash refers to the first label, the leftmost part. For vitalik.eth, the first label is vitalik, so the labelhash describes that fragment. For sub.vitalik.eth, the first label would be sub, while the namehash would still describe the full name sub.vitalik.eth.

Namehash is used to identify full names and subnames in ENS. Labelhash lets you refer to a specific label regardless of which name it appears in. Both results are repeatable as long as the input is the same and has gone through the required normalization.

Limitations: ENSIP-15 Normalization and Unsupported Characters

The calculator uses simple normalization: it trims the name and converts it to lowercase. It does not perform full ENSIP-15 normalization, so emoji, various Unicode characters, and equivalent NFC and NFD forms are not converted to canonical form. This matters if the name contains characters outside the basic set or mixes different alphabets.

• The tool does not check whether a name is registered, available, or owned by you.
• It does not show ENS records, addresses, the owner, or the resolver.
• It does not perform transactions or connect to a wallet.
• It does not support full ENSIP-15 for emoji, Unicode, and NFC/NFD forms — this is noted in the interface.
• Empty labels, such as two dots or a dot at the beginning or end, cause an error.

If your name contains special characters, emoji, or unusual letters, verify it yourself according to ENS rules before using the result in another application. The calculator returns a result for the text you enter and does so locally in your browser. It is not intended for appraising names or trading them.

Frequently Asked Questions

This tool computes hashes locally and does not replace full ENSIP-15 normalization; before using a name in ENS, verify it with official libraries.