Registry / serialization / ethereumjs-util

ethereumjs-util

library7.1.5jsnpmunverified

EthereumJS Util (currently at stable version 10.1.1, with version 7.1.5 referenced in the prompt as a specific historical point) is a foundational utility library within the larger EthereumJS ecosystem. It provides a comprehensive collection of low-level, high-performance functions essential for interacting with the Ethereum blockchain, including cryptographic hashing (e.g., Keccak256), RLP encoding/decoding, address validation (like checksum addresses), byte array manipulation, and elliptic curve operations. It is actively maintained as part of the EthereumJS monorepo, with regular minor and patch releases, and major versions typically aligning with significant Ethereum protocol updates or fundamental architectural shifts (e.g., ESM-only in v7). Its key differentiators include its tight integration and alignment with official Ethereum specifications, extensive TypeScript support, and being a reference implementation for various Ethereum primitives. It re-exports critical libraries like `BN.js` for arbitrary-precision arithmetic and `rlp` for Recursive Length Prefix encoding, making it a central point for many Ethereum-related development tasks.

serialization auth-security data

npm install ethereumjs-util

github ↗package ↗

INSTALL

IMPORT

SIG · ETHEREUMJS-UTIL

ethereumjs-util

serializationjavascriptv7.1.5

Install

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Import

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Disk

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Pass rate

0/ 6

Env Coverage0 / 6

glibc

18–22

musl

18–22

Install & Compatibility

Where this runs

tested against v? · npm install

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

node 18–226 runs

build_error

glibc

node 18–226 runs

build_error

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

isValidChecksumAddress

✓ import { isValidChecksumAddress } from 'ethereumjs-util'

✗ const { isValidChecksumAddress } = require('ethereumjs-util')

Since v7, this package is ESM-only. CommonJS 'require' syntax will not work.

✓ import { BN } from 'ethereumjs-util'

✗ import BN from 'bn.js'

BN.js is re-exported directly from ethereumjs-util for convenience. It is not the default export of BN.js itself.

stripHexPrefix

✓ import { stripHexPrefix } from 'ethereumjs-util'

✗ import { stripHexPrefix } from 'ethjs-util'

Functionality from ethjs-util has been internalized since v7.1.3; import directly from 'ethereumjs-util'.

rlp

✓ import { rlp } from 'ethereumjs-util'

The rlp library is re-exported by ethereumjs-util for direct access.

This quickstart demonstrates basic usage, including Ethereum checksum address validation, byte buffer manipulation, and arbitrary-precision arithmetic using the re-exported BN.js library.

import assert from 'assert'; import { isValidChecksumAddress, unpadBuffer, BN } from 'ethereumjs-util'; // Example 1: Validate an Ethereum checksum address const address = '0x2F015C60E0be116B1f0CD534704Db9c92118FB6A'; const isValid = isValidChecksumAddress(address); console.log(`Address ${address} is valid: ${isValid}`); assert.ok(isValid, 'Checksum address validation failed'); // Example 2: Unpad a Buffer const paddedBuffer = Buffer.from('000000006600', 'hex'); const unpaddedBuffer = unpadBuffer(paddedBuffer); console.log(`Unpadded buffer: ${unpaddedBuffer.toString('hex')}`); assert.ok(unpaddedBuffer.equals(Buffer.from('6600', 'hex')), 'Buffer unpadding failed'); // Example 3: Perform arithmetic with BN.js const bn1 = new BN('dead', 16); // Hexadecimal 'dead' const bn2 = new BN('101010', 2); // Binary '101010' const sum = bn1.add(bn2); const expectedValue = new BN(57047); // Decimal equivalent of 'dead' (57005) + '101010' (42) = 57047 console.log(`BN sum: ${sum.toString()}`); assert.ok(sum.eqn(expectedValue), 'BN arithmetic failed'); console.log('All quickstart assertions passed!');

Debug

Known issues

breakingStarting with version 7.0.0, `ethereumjs-util` is an ESM-only package. Direct `require()` statements will result in runtime errors. Projects must use ES module syntax (`import`) and configure their build tools accordingly.

fix

Migrate your codebase to use ES module `import` syntax. For Node.js, ensure your package.json specifies `"type": "module"` or use a `.mjs` extension for files importing this package.

affects: >=7.0.0

breakingNode.js 18 support has been deprecated across the EthereumJS monorepo, including `@ethereumjs/util`. The minimum required Node.js version is now 20.

fix

Upgrade your Node.js environment to version 20 or higher to maintain compatibility and receive updates.

affects: >=10.1.1

deprecatedThe `createBinaryObject` helper function within the `object` module (src/object.ts) has been marked as deprecated.

fix

Review your usage of `createBinaryObject` and replace it with alternative, actively supported methods for binary object creation or manipulation. The documentation in the `src/object.ts` file or API docs might provide alternatives.

affects: >=7.1.3

gotchaFunctions originally from the `ethjs-util` package have been internalized into `ethereumjs-util` since v7.1.3. While their API remains largely the same, this internalization means that subtle behavioral changes or future deprecations might occur independently of the original `ethjs-util` library.

fix

Continue importing these functions (e.g., `stripHexPrefix`) directly from `ethereumjs-util`. Be aware that their underlying implementation is now managed by EthereumJS.

affects: >=7.1.3

breakingRecent updates in version 10.1.1 include dependency bumps for `@noble/curves` and `@noble/hashes` to v2. While these are indirect dependencies for most users, direct interaction with these libraries or reliance on their previous versions' specific behaviors could lead to breaking changes.

fix

If your project directly or indirectly relies on specific versions or behaviors of `@noble/curves` or `@noble/hashes`, review their v2 changelogs for potential breaking changes and update your code accordingly.

affects: >=10.1.1

Errors

Common errors & fixes

ReferenceError: require is not defined

Attempting to use CommonJS `require()` syntax in an ES module context or with an ES module library.

fix

Change `const { Name } = require('ethereumjs-util')` to `import { Name } from 'ethereumjs-util'`. Ensure your project's `package.json` has `"type": "module"` or that files using `import` have a `.mjs` extension.

TypeError: Invalid hex string (0x<length 0>)

Providing an empty string or incorrectly formatted string where a hex-prefixed hex string is expected by a utility function (e.g., `toBuffer`, `bufferToHex`).

fix

Ensure that hex string inputs are properly formatted, typically with a '0x' prefix and valid hexadecimal characters. If an empty value is intended, pass an empty Buffer or Uint8Array instead of an empty string for byte-related functions.

Error: Invalid checksum address

The provided Ethereum address does not pass the EIP-55 checksum validation.

fix

Double-check the Ethereum address for typos or incorrect casing. Ensure it matches the EIP-55 checksum standard. If you intend to work with non-checksummed addresses, use functions that do not perform checksum validation or convert to lowercase before validation if appropriate for your use case.

Upgrade

Version history

7.1.5latest on npm

Audit

Dependencies

bn.jsrequiredArbitrary-precision arithmetic, re-exported for convenience.

rlprequiredRecursive Length Prefix encoding/decoding, re-exported for convenience.

@noble/curvesrequiredUnderlying elliptic curve cryptography operations, updated to v2 in 10.1.1.

@noble/hashesrequiredCryptographic hashing primitives, updated to v2 in 10.1.1.

Agent activity

17 hits · last 30 days

node

OpenAI (training)

Resources

githubhttps://github.com/ethereumjs/ethereumjs-monorepo ↗

packagehttps://www.npmjs.com/package/ethereumjs-util ↗