noble-hashes

Audited & minimal JS implementation of hash functions, MACs and KDFs.

• 🔒 Audited by an independent security firm
• 🪶 Minimal: 2.8KB (gzipped) sha256, unused code is excluded from your builds
• 🏎 Fast: hand-optimized for caveats of JS engines
• 🔍 Reliable: chained / ACVP tests ensure correctness
• 🔁 No unrolled loops: makes it easier to verify and reduces source code size up to 5x
• 🦘 Includes SHA, RIPEMD, BLAKE, HMAC, HKDF, PBKDF, Scrypt, Argon2
• 🥈 Wrapper with identical API over native WebCrypto

The library's initial development was funded by Ethereum Foundation.

This library belongs to noble cryptography

noble cryptography — high-security, easily auditable set of contained cryptographic libraries and tools.

• Zero or minimal dependencies
• Highly readable TypeScript / JS code
• PGP-signed releases and transparent NPM builds
• All libraries: ciphers, curves, hashes, post-quantum, 5kb secp256k1 / ed25519
• WASM version: awasm-noble
• Check out the homepage for reading resources, documentation, and apps built with noble

Usage

npm install @noble/hashes

deno add jsr:@noble/hashes

We support all major platforms and runtimes. For React Native, you may need a polyfill for getRandomValues. A standalone file noble-hashes.js is also available.

// import * from '@noble/hashes'; // Error: use sub-imports, to ensure small app size
import { sha256 } from '@noble/hashes/sha2.js';
const hash = sha256(Uint8Array.from([0xca, 0xfe, 0x01, 0x23]));

• sha2: sha256, sha384, sha512
• sha3: FIPS, SHAKE, Keccak
• sha3-addons: cSHAKE, KMAC, KT128, TurboSHAKE
• blake1, blake2, blake3
• legacy: sha1, md5, ripemd160
• MACs: hmac | kmac | blake3 key mode
• KDFs: hkdf | pbkdf2 | scrypt | argon2 | eskdf
• webcrypto: friendly wrapper
• utils
• Security | Speed | Contributing & testing | License

Implementations

Hash functions:

• sha256(): receive & return Uint8Array
• sha256.create().update(a).update(b).digest(): support partial updates
• blake3.create({ context: 'e', dkLen: 32 }): can have options
• support little-endian architecture; also experimentally big-endian
• can hash up to 4GB per chunk, with any amount of chunks

sha2: sha256, sha384, sha512 and others

import { sha224, sha256, sha384, sha512, sha512_224, sha512_256 } from '@noble/hashes/sha2.js';
const res = sha256(Uint8Array.from([0xbc]));

sha3: FIPS, SHAKE, Keccak

import {
  sha3_224, sha3_256, sha3_384, sha3_512,
  keccak_224, keccak_256, keccak_384, keccak_512,
  shake128, shake256,
} from '@noble/hashes/sha3.js';
const s = sha3_256(Uint8Array.from([0x10, 0x20, 0x30]));
const shka = shake128(Uint8Array.from([0x10]), { dkLen: 512 });
const shkb = shake256(Uint8Array.from([0x30]), { dkLen: 512 });

sha3-addons: cSHAKE, KMAC, KT128, TurboSHAKE

import {
  cshake128, cshake256, kt128, kt256,
  keccakprg, kmac128, kmac256,
  parallelhash256, tuplehash256,
  turboshake128, turboshake256,
} from '@noble/hashes/sha3-addons.js';
const data = Uint8Array.from([0x10, 0x20, 0x30]);
const ec = cshake128(data, { personalization: new TextEncoder().encode('def') });
const et = turboshake256(data, { D: 0x05 });
// tuplehash(['ab', 'c']) !== tuplehash(['a', 'bc']) !== tuplehash([data])
const eu = tuplehash256([new TextEncoder().encode('ab'), new TextEncoder().encode('c')]);
// Not parallel in JS (similar to blake3 / kt128), added for compat
const ep = parallelhash256(data, { blockLen: 8 });
const ek = kmac256(Uint8Array.from([0xca]), data);
const ekt = kt128(data);
const p = keccakprg(254);
p.addEntropy();
const rand1b = p.randomBytes(32);

blake1, blake2, blake3

import { blake224, blake256, blake384, blake512 } from '@noble/hashes/blake1.js';
import { blake2b, blake2s } from '@noble/hashes/blake2.js';
import { blake3 } from '@noble/hashes/blake3.js';
const ab = Uint8Array.from([0x01]);
blake256(ab);

// blake2 advanced usage
const txt = new TextEncoder();
blake2s(ab, { key: new Uint8Array(32) }); // blake2b keys can be 64 bytes
blake2s(ab, { personalization: txt.encode('pers1234') }); // 16 bytes for blake2b
blake2s(ab, { salt: txt.encode('salt1234') }); // 16 bytes for blake2b

// blake3 advanced usage
blake3(ab, { dkLen: 256 });
blake3(ab, { key: new Uint8Array(32) });
blake3(ab, { context: txt.encode('application-name') });

legacy: sha1, md5, ripemd160

import { md5, ripemd160, sha1 } from '@noble/hashes/legacy.js';
const h = sha1(Uint8Array.from([0x10, 0x20, 0x30]));

hmac

import { hmac } from '@noble/hashes/hmac.js';
import { sha256 } from '@noble/hashes/sha2.js';
const key = new Uint8Array(32).fill(1);
const msg = new Uint8Array(32).fill(2);
const mac1 = hmac(sha256, key, msg);
const mac2 = hmac.create(sha256, key).update(msg).digest();

hkdf

import { hkdf } from '@noble/hashes/hkdf.js';
import { randomBytes } from '@noble/hashes/utils.js';
import { sha256 } from '@noble/hashes/sha2.js';
const inputKey = randomBytes(32);
const salt = randomBytes(32);
const info = new TextEncoder().encode('application-key');
const hk1 = hkdf(sha256, inputKey, salt, info, 32);

// == same as
import { extract, expand } from '@noble/hashes/hkdf.js';
const prk = extract(sha256, inputKey, salt);
const hk2 = expand(sha256, prk, info, 32);

pbkdf2

import { pbkdf2, pbkdf2Async } from '@noble/hashes/pbkdf2.js';
import { sha256 } from '@noble/hashes/sha2.js';
const pbkey1 = pbkdf2(sha256, 'password', 'salt', { c: 524288, dkLen: 32 });
const pbkey2 = await pbkdf2Async(sha256, 'password', 'salt', { c: 524288, dkLen: 32 });
const pbkey3 = await pbkdf2Async(sha256, Uint8Array.from([1, 2, 3]), Uint8Array.from([4, 5, 6]), {
  c: 524288,
  dkLen: 32,
});

scrypt

import { scrypt, scryptAsync } from '@noble/hashes/scrypt.js';
const scr1 = scrypt('password', 'salt', { N: 2 ** 16, r: 8, p: 1, dkLen: 32 });
const scr2 = await scryptAsync('password', 'salt', { N: 2 ** 16, r: 8, p: 1, dkLen: 32 });
const scr3 = await scryptAsync(Uint8Array.from([1, 2, 3]), Uint8Array.from([4, 5, 6]), {
  N: 2 ** 17,
  r: 8,
  p: 1,
  dkLen: 32,
  onProgress(percentage) {
    console.log('progress', percentage);
  },
  // maxmem: 128 * 8 * (2 ** 17 + 1 + 1), // 128 * r * (N + p + 1)
});

• N, r, p are work factors. It is common to only adjust N, while keeping r: 8, p: 1. See the blog post. JS doesn't support parallelization, making increasing p meaningless.
• dkLen is the length of output bytes e.g. 32 or 64
• onProgress can be used with async version of the function to report progress to a user.
• maxmem prevents DoS and defaults to 1GiB + 2KiB (2**30 + 2**11), enough for N: 2**20, r: 8, p: 1. It can be adjusted using formula: 128 * r * (N + p + 1)

On Apple M4, N: 2**16 takes 0.1s and 64MB RAM; each increment of N doubles both, up to N: 2**24 at 27s and 16GB. Mobile phones can be 1x-4x slower.

argon2

import { argon2d, argon2i, argon2id } from '@noble/hashes/argon2.js';
// Defaults to t=3, m=1GiB (specified in KiB), p=1, and a 1GiB maxmem limit.
const arg1 = argon2id('password', 'saltsalt');

eskdf

import { eskdf } from '@noble/hashes/eskdf.js';
const kdf = await eskdf('example-university', 'beginning-new-example');
console.log(kdf.fingerprint);
const key = kdf.deriveChildKey('aes', 0);
kdf.expire();

Experimental KDF for deriving application-specific child keys from a username + password pair, built on scrypt, pbkdf2 and hkdf with fixed work factors. Non-standard: prefer scrypt or argon2 for new designs.

webcrypto: friendly wrapper

import { sha256, sha384, sha512, hmac, hkdf, pbkdf2 } from '@noble/hashes/webcrypto.js';
import { randomBytes } from '@noble/hashes/utils.js';
const whash = await sha256(Uint8Array.from([0xca, 0xfe, 0x01, 0x23]));

const key = new Uint8Array(32).fill(1);
const msg = new Uint8Array(32).fill(2);
const wmac = await hmac(sha256, key, msg);

const inputKey = randomBytes(32);
const salt = randomBytes(32);
const info = new TextEncoder().encode('application-key');
const hk1 = await hkdf(sha256, inputKey, salt, info, 32);

const pbkey1 = await pbkdf2(sha256, 'password', 'salt', { c: 524288, dkLen: 32 });

A thin wrapper over built-in crypto.subtle, mirroring the noble-hashes API and validating inputs, in just 30+ lines of code. Webcrypto methods are always async.

utils

import { bytesToHex as toHex, randomBytes } from '@noble/hashes/utils.js';
console.log(toHex(randomBytes(32)));

• bytesToHex will convert Uint8Array to a hex string
• randomBytes(bytes) will produce cryptographically secure random Uint8Array of length bytes

Specs

• SHA2: RFC 6234
• SHA2-512/256: pdf
• SHA3: FIPS-202
• SHA3-addons: NIST SP 800-185
• SHA3-addons KT128 (KangarooTwelve 🦘, K12) / TurboSHAKE: RFC 9861
• BLAKE1: pdf
• BLAKE2: RFC 7693
• BLAKE3: site
• SHA1: RFC 3174
• MD5: RFC 1321
• RIPEMD160 (ISO/IEC 10118-3)
• HMAC: RFC 2104
• HKDF: RFC 5869
• PBKDF2: RFC 8018
• Scrypt: RFC 7914
• Argon2: RFC 9106

Security

The library has been audited:

• at version 1.0.0, in Jan 2022, independently, by Cure53
  • PDFs: website, in-repo
  • Scope: everything, besides blake3, sha3-addons, sha1 and argon2, which have not been audited
  • The audit has been funded by Ethereum Foundation with help of Nomic Labs

We've started regular AI-assisted self-audits in Apr 2026.

It is tested against official (ACVP / KAT) vectors, cross-library chained hashing, sliding-window length sweeps and property-based tests (fast-check), and is being fuzzed in CI.

If you see anything unusual: investigate and report.

Constant-timeness

We're targetting algorithmic constant time. JIT-compiler and Garbage Collector make "constant time" extremely hard to achieve timing attack resistance in a scripting language. Which means any other JS library can't have constant-timeness. Even statically typed Rust, a language without GC, makes it harder to achieve constant-time for some cases. If your goal is absolute security, don't use any JS lib — including bindings to native ones. Use low-level libraries & languages.

Memory dumping

The library shares state buffers between hash function calls. Library-owned working buffers are zeroed after use, including mutable UTF-8 copies created from password-KDF string inputs. However, if an attacker can read application memory, you are doomed in any case:

• JS strings are immutable and can't be overwritten with zeros — e.g. a password passed to scrypt(password, salt) as a string stays in memory
• Inputs & outputs are re-used across the application and stay in file buffers / memory anyway
• await anything() writes all internal variables (including numbers) to memory, with no guarantee of when they get overwritten — plenty of time for an attacker to read them

Supply chain security

• Commits are signed with PGP keys to prevent forgery. Be sure to verify the commit signatures
• Releases are made transparently through token-less GitHub CI and Trusted Publishing. Be sure to verify the provenance logs for authenticity.
• Rare releasing is practiced to minimize the need for re-audits by end-users.
• Dependencies are minimized, strictly pinned, and changes are checked with npm-diff.
• Dev dependencies are excluded from end-user installs; they’re only used for development and build steps.

For this package, there are 0 dependencies; and a few dev dependencies:

• jsbt contains helpers for building, benchmarking & testing secure JS apps. It is developed by the same author
• prettier, fast-check and typescript are used for code quality / test generation / ts compilation

Randomness

We rely on the built-in crypto.getRandomValues, which is considered a cryptographically secure PRNG.

Browsers have had weaknesses in the past - and could again - but implementing a userspace CSPRNG is even worse, as there’s no reliable userspace source of high-quality entropy.

Quantum computers

Cryptographically relevant quantum computer, if built, will allow to utilize Grover's algorithm to break hashes in 2^{n/2 operations, instead of 2}n.

This means SHA256 should be replaced with SHA512, SHA3-256 with SHA3-512, SHAKE128 with SHAKE256 etc.

Australian ASD prohibits SHA256 and similar hashes after 2030.

Upgrading

Supported node.js versions:

• v2: v20.19+ (ESM-only)
• v1: v14.21+ (ESM & CJS)

v2.0 changelog:

• The package is now ESM-only. ESM can finally be loaded from common.js on node v20.19+
• .js extension must be used for all modules
  • Old: @noble/hashes/sha3
  • New: @noble/hashes/sha3.js
  • This simplifies working in browsers natively without transpilers
• Only allow Uint8Array as hash inputs, prohibit string
  • Strict validation checks improve security
  • To replicate previous behavior, use utils.utf8ToBytes
• Rename / remove some modules for consistency. Previously, sha384 resided in sha512, which was weird
  • sha256, sha512 => sha2.js (consistent with sha3.js)
  • blake2b, blake2s => blake2.js (consistent with blake3.js, blake1.js)
  • ripemd160, sha1, md5 => legacy.js (all low-security hashes are there)
  • _assert => utils.js
  • crypto internal module got removed: use built-in WebCrypto instead
• Improve typescript types & option autocomplete
• Bump compilation target from es2020 to es2022

Contributing & testing

npm install && npm run build && npm test will build the code and run tests.

There are additional slow suites: timing-based DoS tests npm run test:dos, multi-hour large-input tests npm run test:slow, ACVP LDT vectors npm run test:acvp, and memory-intensive KDF tests npm run test:ultra. The 9–17GiB scrypt cases require an explicitly provisioned machine and run separately with npm run test:ultra:scrypt.

test/misc directory contains unrolled implementations (sha3, argon2) and misc helper scripts.

Some hashes are outside of scope of the library:

• Pedersen in micro-zk-proofs
• Poseidon in noble-curves
• Poly1305 & GHash in noble-ciphers

See paulmillr.com/noble for useful resources, articles, documentation and demos related to the library.

Speed

npm run benchmark

Benchmarks measured on Apple M4.

The library could be 3x faster by utilizing loop unrolling. It isn't used because unrolling a) would increase bundle size b) make lib un-readable c) current perf is "fast enough" for most use-cases.

If you need truly exemplar performance, switch to awasm-noble, which does unrolling in an auditable way and allows to achieve 10GB/s BLAKE3.

# 32B
sha256 438 ns
sha512 1219 ns
sha3_256 1853 ns
sha3_512 1864 ns
kt128 1380 ns
kt256 1370 ns
turboshake128 1191 ns
blake256 1335 ns
blake2b 2186 ns
blake2s 1055 ns
blake3 981 ns
ripemd160 563 ns
md5 449 ns
sha1 507 ns
hmac(sha256) 1955 ns
hmac(sha512) 5126 ns
kmac256 6653 ns
blake3(key) 1120 ns

# 1MB
sha256 x 297 mib/sec
sha512 x 130 mib/sec
sha3_256 x 78.1 mib/sec
sha3_512 x 41.9 mib/sec
kt128 x 184 mib/sec
kt256 x 147 mib/sec
turboshake128 x 186 mib/sec
blake256 x 56.7 mib/sec
blake2b x 66.2 mib/sec
blake2s x 62.9 mib/sec
blake3 x 90 mib/sec
ripemd160 x 179 mib/sec
md5 x 275 mib/sec
sha1 x 417 mib/sec
hmac(sha256) x 290 mib/sec
hmac(sha512) x 129 mib/sec
kmac256 x 78.4 mib/sec
blake3(key) x 90.5 mib/sec

# KDF
hkdf(sha256) x 249,100 ops/sec @ 4015 ns/op
blake3(context) x 480,400 ops/sec @ 2081 ns/op
pbkdf2(sha256, c: 2 ** 18) x 5 ops/sec @ 199 ms/op
scrypt(n: 2 ** 19, r: 8, p: 1) x 1 ops/sec @ 751 ms/op
argon2id(t: 1, m: 128MB) x 3 ops/sec @ 276 ms/op

License

The MIT License (MIT)

Copyright (c) 2022 Paul Miller (https://paulmillr.com)

See LICENSE file.