> ## Documentation Index
> Fetch the complete documentation index at: https://voltaire.tevm.sh/llms.txt
> Use this file to discover all available pages before exploring further.

# crypto/Keccak256

> Auto-generated API documentation

[**@tevm/voltaire**](../index.mdx)

***

[@tevm/voltaire](../index.mdx) / crypto/Keccak256

# crypto/Keccak256

## Variables

### DIGEST\_SIZE

> `const` **DIGEST\_SIZE**: `number` = `32`

Defined in: [src/crypto/Keccak256/constants.js:13](https://github.com/evmts/voltaire/blob/bd6ec34405c15ad8cd51d11579d495dc53813482/src/crypto/Keccak256/constants.js#L13)

Digest size in bytes (32 bytes = 256 bits)

#### Since

0.0.0

***

### ~~Keccak256~~

> `const` **Keccak256**: (`input`) => [`Keccak256Hash`](../index/index.mdx#keccak256hash) & `object` = `Keccak256Hash`

Defined in: [src/crypto/Keccak256/Keccak256.js:82](https://github.com/evmts/voltaire/blob/bd6ec34405c15ad8cd51d11579d495dc53813482/src/crypto/Keccak256/Keccak256.js#L82)

#### Type Declaration

##### ~~contractAddress()~~

> **contractAddress**: (`sender`, `nonce`) => `Uint8Array`\<`ArrayBufferLike`>

Compute contract address from deployer and nonce

Uses CREATE formula: keccak256(rlp(\[sender, nonce]))\[12:]

###### Parameters

###### sender

`Uint8Array`\<`ArrayBufferLike`>

Deployer address (20 bytes)

###### nonce

`bigint`

Transaction nonce

###### Returns

`Uint8Array`\<`ArrayBufferLike`>

Contract address (20 bytes)

###### See

[https://voltaire.tevm.sh/crypto](https://voltaire.tevm.sh/crypto) for crypto documentation

###### Since

0.0.0

###### Throws

If sender is not 20 bytes

###### Example

```javascript theme={null}
import * as Keccak256 from './crypto/Keccak256/index.js';
const sender = new Uint8Array(20);
const address = Keccak256.contractAddress(sender, 0n);
```

##### ~~create2Address()~~

> **create2Address**: (`sender`, `salt`, `initCodeHash`) => `Uint8Array`\<`ArrayBufferLike`>

Compute CREATE2 address

Uses CREATE2 formula: keccak256(0xff ++ sender ++ salt ++ keccak256(init\_code))\[12:]

###### Parameters

###### sender

`Uint8Array`\<`ArrayBufferLike`>

Deployer address (20 bytes)

###### salt

`Uint8Array`\<`ArrayBufferLike`>

32-byte salt

###### initCodeHash

`Uint8Array`\<`ArrayBufferLike`>

Hash of initialization code

###### Returns

`Uint8Array`\<`ArrayBufferLike`>

Contract address (20 bytes)

###### See

[https://voltaire.tevm.sh/crypto](https://voltaire.tevm.sh/crypto) for crypto documentation

###### Since

0.0.0

###### Throws

If sender is not 20 bytes

###### Throws

If salt is not 32 bytes

###### Throws

If initCodeHash is not 32 bytes

###### Example

```javascript theme={null}
import * as Keccak256 from './crypto/Keccak256/index.js';
const sender = new Uint8Array(20);
const salt = new Uint8Array(32);
const initCodeHash = new Uint8Array(32);
const address = Keccak256.create2Address(sender, salt, initCodeHash);
```

##### ~~DIGEST\_SIZE~~

> **DIGEST\_SIZE**: `number`

Digest size in bytes (32 bytes = 256 bits)

###### Since

0.0.0

##### ~~from()~~

> **from**: (`input`) => [`Keccak256Hash`](../index/index.mdx#keccak256hash)

Hash input with Keccak-256 (constructor pattern)

Auto-detects input type and hashes accordingly:

* Uint8Array: hash directly
* string starting with 0x: parse as hex
* string: UTF-8 encode then hash

###### Parameters

###### input

Data to hash

`string` | `Uint8Array`\<`ArrayBufferLike`>

###### Returns

[`Keccak256Hash`](../index/index.mdx#keccak256hash)

32-byte hash

###### See

[https://voltaire.tevm.sh/crypto/keccak256](https://voltaire.tevm.sh/crypto/keccak256) for crypto documentation

###### Since

0.0.0

###### Throws

If hex string is invalid

###### Example

```javascript theme={null}
import { Keccak256Hash } from './crypto/Keccak256/index.js';

const hash1 = Keccak256Hash.from("0x1234");      // Hex
const hash2 = Keccak256Hash.from("hello");       // String
const hash3 = Keccak256Hash.from(uint8array);    // Bytes
```

##### ~~fromHex()~~

> **fromHex**: (`hex`) => [`Keccak256Hash`](../index/index.mdx#keccak256hash) = `hashHex`

Hash hex string with Keccak-256

###### Parameters

###### hex

`string`

Hex string to hash (with or without 0x prefix)

###### Returns

[`Keccak256Hash`](../index/index.mdx#keccak256hash)

32-byte hash

###### See

[https://voltaire.tevm.sh/crypto](https://voltaire.tevm.sh/crypto) for crypto documentation

###### Since

0.0.0

###### Throws

If hex string is invalid or has odd length

###### Example

```javascript theme={null}
import { Keccak256Hash } from './crypto/Keccak256/index.js';
const hash = Keccak256Hash.fromHex('0x1234abcd');
```

##### ~~fromString()~~

> **fromString**: (`str`) => [`Keccak256Hash`](../index/index.mdx#keccak256hash) = `hashString`

Hash string with Keccak-256

String is UTF-8 encoded before hashing.

###### Parameters

###### str

`string`

String to hash

###### Returns

[`Keccak256Hash`](../index/index.mdx#keccak256hash)

32-byte hash

###### See

[https://voltaire.tevm.sh/crypto](https://voltaire.tevm.sh/crypto) for crypto documentation

###### Since

0.0.0

###### Throws

###### Example

```javascript theme={null}
import { Keccak256Hash } from './crypto/Keccak256/index.js';
const hash = Keccak256Hash.fromString('hello');
```

##### ~~fromTopic()~~

> **fromTopic**: (`signature`) => [`Keccak256Hash`](../index/index.mdx#keccak256hash) = `topic`

Compute event topic (32-byte Keccak-256 hash)

Used for Ethereum event signatures.

###### Parameters

###### signature

`string`

Event signature string

###### Returns

[`Keccak256Hash`](../index/index.mdx#keccak256hash)

32-byte topic

###### See

[https://voltaire.tevm.sh/crypto](https://voltaire.tevm.sh/crypto) for crypto documentation

###### Since

0.0.0

###### Throws

###### Example

```javascript theme={null}
import { Keccak256Hash } from './crypto/Keccak256/index.js';
const topic = Keccak256Hash.fromTopic('Transfer(address,address,uint256)');
```

##### ~~hash()~~

> **hash**: (`data`) => [`Keccak256Hash`](../index/index.mdx#keccak256hash)

Hash data with Keccak-256

###### Parameters

###### data

`Uint8Array`\<`ArrayBufferLike`>

Data to hash

###### Returns

[`Keccak256Hash`](../index/index.mdx#keccak256hash)

32-byte hash

###### See

[https://voltaire.tevm.sh/crypto](https://voltaire.tevm.sh/crypto) for crypto documentation

###### Since

0.0.0

###### Throws

###### Example

```javascript theme={null}
import { Keccak256Hash } from './crypto/Keccak256/index.js';
const hash = Keccak256Hash.from(data);
```

##### ~~hashHex()~~

> **hashHex**: (`hex`) => [`Keccak256Hash`](../index/index.mdx#keccak256hash)

Hash hex string with Keccak-256

###### Parameters

###### hex

`string`

Hex string to hash (with or without 0x prefix)

###### Returns

[`Keccak256Hash`](../index/index.mdx#keccak256hash)

32-byte hash

###### See

[https://voltaire.tevm.sh/crypto](https://voltaire.tevm.sh/crypto) for crypto documentation

###### Since

0.0.0

###### Throws

If hex string is invalid or has odd length

###### Example

```javascript theme={null}
import { Keccak256Hash } from './crypto/Keccak256/index.js';
const hash = Keccak256Hash.fromHex('0x1234abcd');
```

##### ~~hashMultiple()~~

> **hashMultiple**: (`chunks`) => [`Keccak256Hash`](../index/index.mdx#keccak256hash)

Hash multiple data chunks in sequence

Equivalent to hashing the concatenation of all chunks.

###### Parameters

###### chunks

readonly `Uint8Array`\<`ArrayBufferLike`>\[]

Array of data chunks to hash

###### Returns

[`Keccak256Hash`](../index/index.mdx#keccak256hash)

32-byte hash

###### See

[https://voltaire.tevm.sh/crypto](https://voltaire.tevm.sh/crypto) for crypto documentation

###### Since

0.0.0

###### Throws

###### Example

```javascript theme={null}
import { Keccak256Hash } from './crypto/Keccak256/index.js';
const hash = Keccak256Hash.from(combined);
```

##### ~~hashString()~~

> **hashString**: (`str`) => [`Keccak256Hash`](../index/index.mdx#keccak256hash)

Hash string with Keccak-256

String is UTF-8 encoded before hashing.

###### Parameters

###### str

`string`

String to hash

###### Returns

[`Keccak256Hash`](../index/index.mdx#keccak256hash)

32-byte hash

###### See

[https://voltaire.tevm.sh/crypto](https://voltaire.tevm.sh/crypto) for crypto documentation

###### Since

0.0.0

###### Throws

###### Example

```javascript theme={null}
import { Keccak256Hash } from './crypto/Keccak256/index.js';
const hash = Keccak256Hash.fromString('hello');
```

##### ~~RATE~~

> **RATE**: `number`

Rate in bytes for Keccak256 (136 bytes = 1088 bits)

###### Since

0.0.0

##### ~~selector()~~

> **selector**: (`signature`) => `Uint8Array`\<`ArrayBufferLike`>

Compute function selector (first 4 bytes of Keccak-256 hash)

Used for Ethereum function signatures.

###### Parameters

###### signature

`string`

Function signature string

###### Returns

`Uint8Array`\<`ArrayBufferLike`>

4-byte selector

###### See

[https://voltaire.tevm.sh/crypto](https://voltaire.tevm.sh/crypto) for crypto documentation

###### Since

0.0.0

###### Throws

###### Example

```javascript theme={null}
import * as Keccak256 from './crypto/Keccak256/index.js';
const selector = Keccak256.selector('transfer(address,uint256)');
// Uint8Array(4) [0xa9, 0x05, 0x9c, 0xbb]
```

##### ~~STATE\_SIZE~~

> **STATE\_SIZE**: `number`

State size (25 u64 words = 1600 bits)

###### Since

0.0.0

##### ~~topic()~~

> **topic**: (`signature`) => [`Keccak256Hash`](../index/index.mdx#keccak256hash)

Compute event topic (32-byte Keccak-256 hash)

Used for Ethereum event signatures.

###### Parameters

###### signature

`string`

Event signature string

###### Returns

[`Keccak256Hash`](../index/index.mdx#keccak256hash)

32-byte topic

###### See

[https://voltaire.tevm.sh/crypto](https://voltaire.tevm.sh/crypto) for crypto documentation

###### Since

0.0.0

###### Throws

###### Example

```javascript theme={null}
import { Keccak256Hash } from './crypto/Keccak256/index.js';
const topic = Keccak256Hash.fromTopic('Transfer(address,address,uint256)');
```

#### Deprecated

Use Keccak256Hash instead
Keccak256 alias maintained for backward compatibility

***

### RATE

> `const` **RATE**: `number` = `136`

Defined in: [src/crypto/Keccak256/constants.js:20](https://github.com/evmts/voltaire/blob/bd6ec34405c15ad8cd51d11579d495dc53813482/src/crypto/Keccak256/constants.js#L20)

Rate in bytes for Keccak256 (136 bytes = 1088 bits)

#### Since

0.0.0

***

### STATE\_SIZE

> `const` **STATE\_SIZE**: `number` = `25`

Defined in: [src/crypto/Keccak256/constants.js:27](https://github.com/evmts/voltaire/blob/bd6ec34405c15ad8cd51d11579d495dc53813482/src/crypto/Keccak256/constants.js#L27)

State size (25 u64 words = 1600 bits)

#### Since

0.0.0

## Functions

### contractAddress()

> **contractAddress**(`sender`, `nonce`): `Uint8Array`\<`ArrayBufferLike`>

Defined in: [src/crypto/Keccak256/contractAddress.js:40](https://github.com/evmts/voltaire/blob/bd6ec34405c15ad8cd51d11579d495dc53813482/src/crypto/Keccak256/contractAddress.js#L40)

Compute contract address from deployer and nonce

Uses CREATE formula: keccak256(rlp(\[sender, nonce]))\[12:]

#### Parameters

##### sender

`Uint8Array`\<`ArrayBufferLike`>

Deployer address (20 bytes)

##### nonce

`bigint`

Transaction nonce

#### Returns

`Uint8Array`\<`ArrayBufferLike`>

Contract address (20 bytes)

#### See

[https://voltaire.tevm.sh/crypto](https://voltaire.tevm.sh/crypto) for crypto documentation

#### Since

0.0.0

#### Throws

If sender is not 20 bytes

#### Example

```javascript theme={null}
import * as Keccak256 from './crypto/Keccak256/index.js';
const sender = new Uint8Array(20);
const address = Keccak256.contractAddress(sender, 0n);
```

***

### create2Address()

> **create2Address**(`sender`, `salt`, `initCodeHash`): `Uint8Array`\<`ArrayBufferLike`>

Defined in: [src/crypto/Keccak256/create2Address.js:27](https://github.com/evmts/voltaire/blob/bd6ec34405c15ad8cd51d11579d495dc53813482/src/crypto/Keccak256/create2Address.js#L27)

Compute CREATE2 address

Uses CREATE2 formula: keccak256(0xff ++ sender ++ salt ++ keccak256(init\_code))\[12:]

#### Parameters

##### sender

`Uint8Array`\<`ArrayBufferLike`>

Deployer address (20 bytes)

##### salt

`Uint8Array`\<`ArrayBufferLike`>

32-byte salt

##### initCodeHash

`Uint8Array`\<`ArrayBufferLike`>

Hash of initialization code

#### Returns

`Uint8Array`\<`ArrayBufferLike`>

Contract address (20 bytes)

#### See

[https://voltaire.tevm.sh/crypto](https://voltaire.tevm.sh/crypto) for crypto documentation

#### Since

0.0.0

#### Throws

If sender is not 20 bytes

#### Throws

If salt is not 32 bytes

#### Throws

If initCodeHash is not 32 bytes

#### Example

```javascript theme={null}
import * as Keccak256 from './crypto/Keccak256/index.js';
const sender = new Uint8Array(20);
const salt = new Uint8Array(32);
const initCodeHash = new Uint8Array(32);
const address = Keccak256.create2Address(sender, salt, initCodeHash);
```

***

### from()

> **from**(`input`): [`Keccak256Hash`](../index/index.mdx#keccak256hash)

Defined in: [src/crypto/Keccak256/from.js:27](https://github.com/evmts/voltaire/blob/bd6ec34405c15ad8cd51d11579d495dc53813482/src/crypto/Keccak256/from.js#L27)

Hash input with Keccak-256 (constructor pattern)

Auto-detects input type and hashes accordingly:

* Uint8Array: hash directly
* string starting with 0x: parse as hex
* string: UTF-8 encode then hash

#### Parameters

##### input

Data to hash

`string` | `Uint8Array`\<`ArrayBufferLike`>

#### Returns

[`Keccak256Hash`](../index/index.mdx#keccak256hash)

32-byte hash

#### See

[https://voltaire.tevm.sh/crypto/keccak256](https://voltaire.tevm.sh/crypto/keccak256) for crypto documentation

#### Since

0.0.0

#### Throws

If hex string is invalid

#### Example

```javascript theme={null}
import { Keccak256Hash } from './crypto/Keccak256/index.js';

const hash1 = Keccak256Hash.from("0x1234");      // Hex
const hash2 = Keccak256Hash.from("hello");       // String
const hash3 = Keccak256Hash.from(uint8array);    // Bytes
```

***

### hash()

> **hash**(`data`): [`Keccak256Hash`](../index/index.mdx#keccak256hash)

Defined in: [src/crypto/Keccak256/hash.js:17](https://github.com/evmts/voltaire/blob/bd6ec34405c15ad8cd51d11579d495dc53813482/src/crypto/Keccak256/hash.js#L17)

Hash data with Keccak-256

#### Parameters

##### data

`Uint8Array`\<`ArrayBufferLike`>

Data to hash

#### Returns

[`Keccak256Hash`](../index/index.mdx#keccak256hash)

32-byte hash

#### See

[https://voltaire.tevm.sh/crypto](https://voltaire.tevm.sh/crypto) for crypto documentation

#### Since

0.0.0

#### Throws

#### Example

```javascript theme={null}
import { Keccak256Hash } from './crypto/Keccak256/index.js';
const hash = Keccak256Hash.from(data);
```

***

### hashHex()

> **hashHex**(`hex`): [`Keccak256Hash`](../index/index.mdx#keccak256hash)

Defined in: [src/crypto/Keccak256/hashHex.js:18](https://github.com/evmts/voltaire/blob/bd6ec34405c15ad8cd51d11579d495dc53813482/src/crypto/Keccak256/hashHex.js#L18)

Hash hex string with Keccak-256

#### Parameters

##### hex

`string`

Hex string to hash (with or without 0x prefix)

#### Returns

[`Keccak256Hash`](../index/index.mdx#keccak256hash)

32-byte hash

#### See

[https://voltaire.tevm.sh/crypto](https://voltaire.tevm.sh/crypto) for crypto documentation

#### Since

0.0.0

#### Throws

If hex string is invalid or has odd length

#### Example

```javascript theme={null}
import { Keccak256Hash } from './crypto/Keccak256/index.js';
const hash = Keccak256Hash.fromHex('0x1234abcd');
```

***

### hashMultiple()

> **hashMultiple**(`chunks`): [`Keccak256Hash`](../index/index.mdx#keccak256hash)

Defined in: [src/crypto/Keccak256/hashMultiple.js:19](https://github.com/evmts/voltaire/blob/bd6ec34405c15ad8cd51d11579d495dc53813482/src/crypto/Keccak256/hashMultiple.js#L19)

Hash multiple data chunks in sequence

Equivalent to hashing the concatenation of all chunks.

#### Parameters

##### chunks

readonly `Uint8Array`\<`ArrayBufferLike`>\[]

Array of data chunks to hash

#### Returns

[`Keccak256Hash`](../index/index.mdx#keccak256hash)

32-byte hash

#### See

[https://voltaire.tevm.sh/crypto](https://voltaire.tevm.sh/crypto) for crypto documentation

#### Since

0.0.0

#### Throws

#### Example

```javascript theme={null}
import { Keccak256Hash } from './crypto/Keccak256/index.js';
const hash = Keccak256Hash.from(combined);
```

***

### hashString()

> **hashString**(`str`): [`Keccak256Hash`](../index/index.mdx#keccak256hash)

Defined in: [src/crypto/Keccak256/hashString.js:19](https://github.com/evmts/voltaire/blob/bd6ec34405c15ad8cd51d11579d495dc53813482/src/crypto/Keccak256/hashString.js#L19)

Hash string with Keccak-256

String is UTF-8 encoded before hashing.

#### Parameters

##### str

`string`

String to hash

#### Returns

[`Keccak256Hash`](../index/index.mdx#keccak256hash)

32-byte hash

#### See

[https://voltaire.tevm.sh/crypto](https://voltaire.tevm.sh/crypto) for crypto documentation

#### Since

0.0.0

#### Throws

#### Example

```javascript theme={null}
import { Keccak256Hash } from './crypto/Keccak256/index.js';
const hash = Keccak256Hash.fromString('hello');
```

***

### selector()

> **selector**(`signature`): `Uint8Array`\<`ArrayBufferLike`>

Defined in: [src/crypto/Keccak256/selector.js:20](https://github.com/evmts/voltaire/blob/bd6ec34405c15ad8cd51d11579d495dc53813482/src/crypto/Keccak256/selector.js#L20)

Compute function selector (first 4 bytes of Keccak-256 hash)

Used for Ethereum function signatures.

#### Parameters

##### signature

`string`

Function signature string

#### Returns

`Uint8Array`\<`ArrayBufferLike`>

4-byte selector

#### See

[https://voltaire.tevm.sh/crypto](https://voltaire.tevm.sh/crypto) for crypto documentation

#### Since

0.0.0

#### Throws

#### Example

```javascript theme={null}
import * as Keccak256 from './crypto/Keccak256/index.js';
const selector = Keccak256.selector('transfer(address,uint256)');
// Uint8Array(4) [0xa9, 0x05, 0x9c, 0xbb]
```

***

### topic()

> **topic**(`signature`): [`Keccak256Hash`](../index/index.mdx#keccak256hash)

Defined in: [src/crypto/Keccak256/topic.js:19](https://github.com/evmts/voltaire/blob/bd6ec34405c15ad8cd51d11579d495dc53813482/src/crypto/Keccak256/topic.js#L19)

Compute event topic (32-byte Keccak-256 hash)

Used for Ethereum event signatures.

#### Parameters

##### signature

`string`

Event signature string

#### Returns

[`Keccak256Hash`](../index/index.mdx#keccak256hash)

32-byte topic

#### See

[https://voltaire.tevm.sh/crypto](https://voltaire.tevm.sh/crypto) for crypto documentation

#### Since

0.0.0

#### Throws

#### Example

```javascript theme={null}
import { Keccak256Hash } from './crypto/Keccak256/index.js';
const topic = Keccak256Hash.fromTopic('Transfer(address,address,uint256)');
```

## References

### Keccak256Hash

Re-exports [Keccak256Hash](../index/index.mdx#keccak256hash)