docs

@ethereumjs/util

@ethereumjs/util

Table of contents

Enumerations

• KeyEncoding
• TypeOutput
• ValueEncoding

Classes

• Account
• Address
• AsyncEventEmitter
• Lock
• MapDB
• Withdrawal

Interfaces

• AccountData
• DB
• DelBatch
• ECDSASignature
• EthersProvider
• EventMap
• GenesisState
• JsonRpcWithdrawal
• Kzg
• PutBatch
• TransformabletoBytes

Type Aliases

• AccountBodyBytes
• AccountState
• AddressLike
• BatchDBOp
• BigIntLike
• BytesLike
• DBObject
• EncodingOpts
• NestedUint8Array
• PrefixedHexString
• StoragePair
• ToBytesInputTypes
• TypeOutputReturnType
• WithdrawalBytes
• WithdrawalData

Variables

• BIGINT_0
• BIGINT_1
• BIGINT_100
• BIGINT_128
• BIGINT_160
• BIGINT_2
• BIGINT_224
• BIGINT_255
• BIGINT_256
• BIGINT_27
• BIGINT_28
• BIGINT_2EXP160
• BIGINT_2EXP224
• BIGINT_2EXP256
• BIGINT_2EXP96
• BIGINT_3
• BIGINT_31
• BIGINT_32
• BIGINT_64
• BIGINT_7
• BIGINT_8
• BIGINT_96
• BIGINT_NEG1
• GWEI_TO_WEI
• KECCAK256_NULL
• KECCAK256_NULL_S
• KECCAK256_RLP
• KECCAK256_RLP_ARRAY
• KECCAK256_RLP_ARRAY_S
• KECCAK256_RLP_S
• MAX_INTEGER
• MAX_INTEGER_BIGINT
• MAX_UINT64
• MAX_WITHDRAWALS_PER_PAYLOAD
• RIPEMD160_ADDRESS_STRING
• RLP_EMPTY_STRING
• SECP256K1_ORDER
• SECP256K1_ORDER_DIV_2
• TWO_POW256
• kzg

Functions

• accountBodyFromSlim
• accountBodyToRLP
• accountBodyToSlim
• addHexPrefix
• arrayContainsArray
• bigInt64ToBytes
• bigIntMax
• bigIntMin
• bigIntToBytes
• bigIntToHex
• bigIntToUnpaddedBytes
• blobsToCommitments
• blobsToProofs
• bytesToBigInt
• bytesToBigInt64
• bytesToHex
• bytesToInt
• bytesToInt32
• bytesToUnprefixedHex
• bytesToUtf8
• calculateSigRecovery
• commitmentsToVersionedHashes
• compareBytes
• computeVersionedHash
• concatBytes
• ecrecover
• ecsign
• equalsBytes
• fetchFromProvider
• formatBigDecimal
• fromAscii
• fromRpcSig
• fromSigned
• fromUtf8
• generateAddress
• generateAddress2
• getBinarySize
• getBlobs
• getKeys
• getProvider
• hashPersonalMessage
• hexToBytes
• importPublic
• initKZG
• int32ToBytes
• intToBytes
• intToHex
• intToUnpaddedBytes
• isHexPrefixed
• isHexString
• isValidAddress
• isValidChecksumAddress
• isValidPrivate
• isValidPublic
• isValidSignature
• isZeroAddress
• padToEven
• parseGethGenesisState
• privateToAddress
• privateToPublic
• pubToAddress
• publicToAddress
• randomBytes
• setLengthLeft
• setLengthRight
• short
• stripHexPrefix
• toAscii
• toBytes
• toChecksumAddress
• toCompactSig
• toRpcSig
• toType
• toUnsigned
• unpadArray
• unpadBytes
• unpadHex
• unprefixedHexToBytes
• utf8ToBytes
• validateNoLeadingZeroes
• zeroAddress
• zeros

Type Aliases

AccountBodyBytes

Ƭ AccountBodyBytes: [Uint8Array, Uint8Array, Uint8Array, Uint8Array]

Defined in

packages/util/src/account.ts:29

---

AccountState

Ƭ AccountState: [balance: PrefixedHexString, code: PrefixedHexString, storage: StoragePair[], nonce: PrefixedHexString]

Defined in

packages/util/src/genesis.ts:8

---

AddressLike

Ƭ AddressLike: Address | Uint8Array | PrefixedHexString

A type that represents an input that can be converted to an Address.

Defined in

packages/util/src/types.ts:31

---

BatchDBOp

Ƭ BatchDBOp<TKey, TValue>: PutBatch<TKey, TValue> | DelBatch<TKey>

Type parameters

Name	Type
TKey	extends Uint8Array | string | number = Uint8Array
TValue	extends Uint8Array | string | DBObject = Uint8Array

Defined in

packages/util/src/db.ts:4

---

BigIntLike

Ƭ BigIntLike: bigint | PrefixedHexString | number | Uint8Array

Defined in

packages/util/src/types.ts:10

---

BytesLike

Ƭ BytesLike: Uint8Array | number[] | number | bigint | TransformabletoBytes | PrefixedHexString

Defined in

packages/util/src/types.ts:15

---

DBObject

Ƭ DBObject: Object

Index signature

▪ [key: string]: string | string[] | number

Defined in

packages/util/src/db.ts:1

---

EncodingOpts

Ƭ EncodingOpts: Object

Type declaration

Name	Type
keyEncoding?	KeyEncoding
valueEncoding?	ValueEncoding

Defined in

packages/util/src/db.ts:21

---

NestedUint8Array

Ƭ NestedUint8Array: (Uint8Array | NestedUint8Array)[]

Defined in

packages/util/src/types.ts:37

---

PrefixedHexString

Ƭ PrefixedHexString: string

Defined in

packages/util/src/types.ts:26

---

StoragePair

Ƭ StoragePair: [key: PrefixedHexString, value: PrefixedHexString]

Defined in

packages/util/src/genesis.ts:6

---

ToBytesInputTypes

Ƭ ToBytesInputTypes: PrefixedHexString | number | bigint | Uint8Array | number[] | TransformabletoBytes | null | undefined

Defined in

packages/util/src/bytes.ts:267

---

TypeOutputReturnType

Ƭ TypeOutputReturnType: Object

Type declaration

Name	Type
0	number
1	bigint
2	Uint8Array
3	PrefixedHexString

Defined in

packages/util/src/types.ts:49

---

WithdrawalBytes

Ƭ WithdrawalBytes: [Uint8Array, Uint8Array, Uint8Array, Uint8Array]

Defined in

packages/util/src/withdrawal.ts:30

---

WithdrawalData

Ƭ WithdrawalData: Object

Flexible input data type for EIP-4895 withdrawal data with amount in Gwei to match CL representation and for eventual ssz withdrawalsRoot

Type declaration

Name	Type
address	AddressLike
amount	BigIntLike
index	BigIntLike
validatorIndex	BigIntLike

Defined in

packages/util/src/withdrawal.ts:12

Variables

BIGINT_0

• Const BIGINT_0: bigint

Defined in

packages/util/src/constants.ts:82

---

BIGINT_1

• Const BIGINT_1: bigint

Defined in

packages/util/src/constants.ts:83

---

BIGINT_100

• Const BIGINT_100: bigint

Defined in

packages/util/src/constants.ts:100

---

BIGINT_128

• Const BIGINT_128: bigint

Defined in

packages/util/src/constants.ts:95

---

BIGINT_160

• Const BIGINT_160: bigint

Defined in

packages/util/src/constants.ts:101

---

BIGINT_2

• Const BIGINT_2: bigint

Defined in

packages/util/src/constants.ts:84

---

BIGINT_224

• Const BIGINT_224: bigint

Defined in

packages/util/src/constants.ts:102

---

BIGINT_255

• Const BIGINT_255: bigint

Defined in

packages/util/src/constants.ts:96

---

BIGINT_256

• Const BIGINT_256: bigint

Defined in

packages/util/src/constants.ts:97

---

BIGINT_27

• Const BIGINT_27: bigint

Defined in

packages/util/src/constants.ts:89

---

BIGINT_28

• Const BIGINT_28: bigint

Defined in

packages/util/src/constants.ts:90

---

BIGINT_2EXP160

• Const BIGINT_2EXP160: bigint

Defined in

packages/util/src/constants.ts:104

---

BIGINT_2EXP224

• Const BIGINT_2EXP224: bigint

Defined in

packages/util/src/constants.ts:105

---

BIGINT_2EXP256

• Const BIGINT_2EXP256: bigint

Defined in

packages/util/src/constants.ts:107

---

BIGINT_2EXP96

• Const BIGINT_2EXP96: bigint

Defined in

packages/util/src/constants.ts:103

---

BIGINT_3

• Const BIGINT_3: bigint

Defined in

packages/util/src/constants.ts:85

---

BIGINT_31

• Const BIGINT_31: bigint

Defined in

packages/util/src/constants.ts:91

---

BIGINT_32

• Const BIGINT_32: bigint

Defined in

packages/util/src/constants.ts:92

---

BIGINT_64

• Const BIGINT_64: bigint

Defined in

packages/util/src/constants.ts:93

---

BIGINT_7

• Const BIGINT_7: bigint

Defined in

packages/util/src/constants.ts:86

---

BIGINT_8

• Const BIGINT_8: bigint

Defined in

packages/util/src/constants.ts:87

---

BIGINT_96

• Const BIGINT_96: bigint

Defined in

packages/util/src/constants.ts:99

---

BIGINT_NEG1

• Const BIGINT_NEG1: bigint

BigInt constants

Defined in

packages/util/src/constants.ts:80

---

GWEI_TO_WEI

• Const GWEI_TO_WEI: bigint

Easy conversion from Gwei to wei

Defined in

packages/util/src/units.ts:3

---

KECCAK256_NULL

• Const KECCAK256_NULL: Uint8Array

Keccak-256 hash of null

Defined in

packages/util/src/constants.ts:44

---

KECCAK256_NULL_S

• Const KECCAK256_NULL_S: "0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470"

Keccak-256 hash of null

Defined in

packages/util/src/constants.ts:39

---

KECCAK256_RLP

• Const KECCAK256_RLP: Uint8Array

Keccak-256 hash of the RLP of null

Defined in

packages/util/src/constants.ts:65

---

KECCAK256_RLP_ARRAY

• Const KECCAK256_RLP_ARRAY: Uint8Array

Keccak-256 of an RLP of an empty array

Defined in

packages/util/src/constants.ts:55

---

KECCAK256_RLP_ARRAY_S

• Const KECCAK256_RLP_ARRAY_S: "0x1dcc4de8dec75d7aab85b567b6ccd41ad312451b948a7413f0a142fd40d49347"

Keccak-256 of an RLP of an empty array

Defined in

packages/util/src/constants.ts:49

---

KECCAK256_RLP_S

• Const KECCAK256_RLP_S: "0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421"

Keccak-256 hash of the RLP of null

Defined in

packages/util/src/constants.ts:60

---

MAX_INTEGER

• Const MAX_INTEGER: bigint

The max integer that the evm can handle (2^256-1)

Defined in

packages/util/src/constants.ts:13

---

MAX_INTEGER_BIGINT

• Const MAX_INTEGER_BIGINT: bigint

The max integer that the evm can handle (2^256-1) as a bigint 2^256-1 equals to 340282366920938463463374607431768211455 We use literal value instead of calculated value for compatibility issue.

Defined in

packages/util/src/constants.ts:22

---

MAX_UINT64

• Const MAX_UINT64: bigint

2^64-1

Defined in

packages/util/src/constants.ts:8

---

MAX_WITHDRAWALS_PER_PAYLOAD

• Const MAX_WITHDRAWALS_PER_PAYLOAD: 16

Defined in

packages/util/src/constants.ts:72

---

RIPEMD160_ADDRESS_STRING

• Const RIPEMD160_ADDRESS_STRING: "0000000000000000000000000000000000000003"

Defined in

packages/util/src/constants.ts:74

---

RLP_EMPTY_STRING

• Const RLP_EMPTY_STRING: Uint8Array

RLP encoded empty string

Defined in

packages/util/src/constants.ts:70

---

SECP256K1_ORDER

• Const SECP256K1_ORDER: bigint = secp256k1.CURVE.n

Defined in

packages/util/src/constants.ts:26

---

SECP256K1_ORDER_DIV_2

• Const SECP256K1_ORDER_DIV_2: bigint

Defined in

packages/util/src/constants.ts:27

---

TWO_POW256

• Const TWO_POW256: bigint

2^256

Defined in

packages/util/src/constants.ts:32

---

kzg

• kzg: Kzg

Defined in

packages/util/src/kzg.ts:26

Functions

accountBodyFromSlim

▸ accountBodyFromSlim(body): Uint8Array[]

Parameters

Name	Type
body	AccountBodyBytes

Returns

Uint8Array[]

Defined in

packages/util/src/account.ts:357

---

accountBodyToRLP

▸ accountBodyToRLP(body, couldBeSlim?): Uint8Array

Converts a slim account (per snap protocol spec) to the RLP encoded version of the account

Parameters

Name	Type	Default value	Description
body	AccountBodyBytes	undefined	Array of 4 Uint8Array-like items to represent the account
couldBeSlim	boolean	true	-

Returns

Uint8Array

RLP encoded version of the account

Defined in

packages/util/src/account.ts:383

---

accountBodyToSlim

▸ accountBodyToSlim(body): Uint8Array[]

Parameters

Name	Type
body	AccountBodyBytes

Returns

Uint8Array[]

Defined in

packages/util/src/account.ts:368

---

addHexPrefix

▸ addHexPrefix(str): string

Adds "0x" to a given string if it does not already start with "0x".

Parameters

Name	Type
str	string

Returns

string

Defined in

packages/util/src/bytes.ts:347

---

arrayContainsArray

▸ arrayContainsArray(superset, subset, some?): boolean

Returns TRUE if the first specified array contains all elements from the second one. FALSE otherwise.

Parameters

Name	Type
superset	unknown[]
subset	unknown[]
some?	boolean

Returns

boolean

Defined in

packages/util/src/internal.ts:91

---

bigInt64ToBytes

▸ bigInt64ToBytes(value, littleEndian?): Uint8Array

Notice

Convert a 64-bit bigint to a Uint8Array.

Parameters

Name	Type	Default value	Description
value	bigint	undefined	The 64-bit bigint to convert.
littleEndian	boolean	false	True for little-endian, undefined or false for big-endian.

Returns

Uint8Array

A Uint8Array of length 8 containing the bigint.

Defined in

packages/util/src/bytes.ts:529

---

bigIntMax

▸ bigIntMax(...args): bigint

Calculates max bigint from an array of bigints

Parameters

Name	Type	Description
...args	bigint[]	array of bigints

Returns

bigint

Defined in

packages/util/src/bytes.ts:409

---

bigIntMin

▸ bigIntMin(...args): bigint

Calculates min BigInt from an array of BigInts

Parameters

Name	Type	Description
...args	bigint[]	array of bigints

Returns

bigint

Defined in

packages/util/src/bytes.ts:415

---

bigIntToBytes

▸ bigIntToBytes(num, littleEndian?): Uint8Array

Converts a bigint to a Uint8Array *

Parameters

Name	Type	Default value	Description
num	bigint	undefined	the bigint to convert
littleEndian	boolean	false	-

Returns

Uint8Array

Defined in

packages/util/src/bytes.ts:156

---

bigIntToHex

▸ bigIntToHex(num): string

Converts a bigint to a 0x prefixed hex string

Parameters

Name	Type	Description
num	bigint	the bigint to convert

Returns

string

Defined in

packages/util/src/bytes.ts:401

---

bigIntToUnpaddedBytes

▸ bigIntToUnpaddedBytes(value): Uint8Array

Convert value from bigint to an unpadded Uint8Array (useful for RLP transport)

Parameters

Name	Type	Description
value	bigint	the bigint to convert

Returns

Uint8Array

Defined in

packages/util/src/bytes.ts:423

---

blobsToCommitments

▸ blobsToCommitments(blobs): Uint8Array[]

Parameters

Name	Type
blobs	Uint8Array[]

Returns

Uint8Array[]

Defined in

packages/util/src/blobs.ts:58

---

blobsToProofs

▸ blobsToProofs(blobs, commitments): Uint8Array[]

Parameters

Name	Type
blobs	Uint8Array[]
commitments	Uint8Array[]

Returns

Uint8Array[]

Defined in

packages/util/src/blobs.ts:66

---

bytesToBigInt

▸ bytesToBigInt(bytes, littleEndian?): bigint

Converts a Uint8Array to a bigint

Parameters

Name	Type	Default value	Description
bytes	Uint8Array	undefined	the bytes to convert
littleEndian	boolean	false	-

Returns

bigint

Defined in

packages/util/src/bytes.ts:80

---

bytesToBigInt64

▸ bytesToBigInt64(bytes, littleEndian?): bigint

Notice

Convert a Uint8Array to a 64-bit bigint

Parameters

Name	Type	Default value	Description
bytes	Uint8Array	undefined	The input Uint8Array from which to read the 64-bit bigint.
littleEndian	boolean	false	True for little-endian, undefined or false for big-endian.

Returns

bigint

The 64-bit bigint read from the input Uint8Array.

Defined in

packages/util/src/bytes.ts:502

---

bytesToHex

▸ bytesToHex(bytes): string

Parameters

Name	Type
bytes	Uint8Array

Returns

string

Defined in

packages/util/src/bytes.ts:60

---

bytesToInt

▸ bytesToInt(bytes): number

Converts a Uint8Array to a number.

Throws

If the input number exceeds 53 bits.

Parameters

Name	Type	Description
bytes	Uint8Array	the bytes to convert

Returns

number

Defined in

packages/util/src/bytes.ts:104

---

bytesToInt32

▸ bytesToInt32(bytes, littleEndian?): number

Notice

Convert a Uint8Array to a 32-bit integer

Parameters

Name	Type	Default value	Description
bytes	Uint8Array	undefined	The input Uint8Array from which to read the 32-bit integer.
littleEndian	boolean	false	True for little-endian, undefined or false for big-endian.

Returns

number

The 32-bit integer read from the input Uint8Array.

Defined in

packages/util/src/bytes.ts:488

---

bytesToUnprefixedHex

▸ bytesToUnprefixedHex(bytes): string

Example

bytesToHex(Uint8Array.from([0xca, 0xfe, 0x01, 0x23])) // 'cafe0123'

Parameters

Name	Type
bytes	Uint8Array

Returns

string

Defined in

node_modules/@noble/hashes/utils.d.ts:11

---

bytesToUtf8

▸ bytesToUtf8(data): string

Parameters

Name	Type
data	Uint8Array

Returns

string

Defined in

node_modules/ethereum-cryptography/utils.d.ts:5

---

calculateSigRecovery

▸ calculateSigRecovery(v, chainId?): bigint

Parameters

Name	Type
v	bigint
chainId?	bigint

Returns

bigint

Defined in

packages/util/src/signature.ts:53

---

commitmentsToVersionedHashes

▸ commitmentsToVersionedHashes(commitments): Uint8Array[]

Generate an array of versioned hashes from corresponding kzg commitments

Parameters

Name	Type	Description
commitments	Uint8Array[]	array of kzg commitments

Returns

Uint8Array[]

array of versioned hashes Note: assumes KZG commitments (version 1 version hashes)

Defined in

packages/util/src/blobs.ts:93

---

compareBytes

▸ compareBytes(value1, value2): number

Compares two Uint8Arrays and returns a number indicating their order in a sorted array.

Parameters

Name	Type	Description
value1	Uint8Array	The first Uint8Array to compare.
value2	Uint8Array	The second Uint8Array to compare.

Returns

number

A positive number if value1 is larger than value2, A negative number if value1 is smaller than value2, or 0 if value1 and value2 are equal.

Defined in

packages/util/src/bytes.ts:446

---

computeVersionedHash

▸ computeVersionedHash(commitment, blobCommitmentVersion): Uint8Array

Converts a vector commitment for a given data blob to its versioned hash. For 4844, this version number will be 0x01 for KZG vector commitments but could be different if future vector commitment types are introduced

Parameters

Name	Type	Description
commitment	Uint8Array	a vector commitment to a blob
blobCommitmentVersion	number	the version number corresponding to the type of vector commitment

Returns

Uint8Array

a versioned hash corresponding to a given blob vector commitment

Defined in

packages/util/src/blobs.ts:80

---

concatBytes

▸ concatBytes(...arrays): Uint8Array

This mirrors the functionality of the ethereum-cryptography export except it skips the check to validate that every element of arrays is indead a uint8Array Can give small performance gains on large arrays

Parameters

Name	Type	Description
...arrays	Uint8Array[]	an array of Uint8Arrays

Returns

Uint8Array

one Uint8Array with all the elements of the original set works like Buffer.concat

Defined in

packages/util/src/bytes.ts:470

---

ecrecover

▸ ecrecover(msgHash, v, r, s, chainId?): Uint8Array

ECDSA public key recovery from signature. NOTE: Accepts v === 0 | v === 1 for EIP1559 transactions

Parameters

Name	Type
msgHash	Uint8Array
v	bigint
r	Uint8Array
s	Uint8Array
chainId?	bigint

Returns

Uint8Array

Recovered public key

Defined in

packages/util/src/signature.ts:71

---

ecsign

▸ ecsign(msgHash, privateKey, chainId?): ECDSASignature

Returns the ECDSA signature of a message hash.

If chainId is provided assume an EIP-155-style signature and calculate the v value accordingly, otherwise return a "static" v just derived from the recovery bit

Parameters

Name	Type
msgHash	Uint8Array
privateKey	Uint8Array
chainId?	bigint

Returns

ECDSASignature

Defined in

packages/util/src/signature.ts:35

---

equalsBytes

▸ equalsBytes(a, b): boolean

Parameters

Name	Type
a	Uint8Array
b	Uint8Array

Returns

boolean

Defined in

node_modules/ethereum-cryptography/utils.d.ts:7

---

fetchFromProvider

▸ fetchFromProvider(url, params): Promise<any>

Makes a simple RPC call to a remote Ethereum JSON-RPC provider and passes through the response. No parameter or response validation is done.

Example

const provider = 'https://mainnet.infura.io/v3/...'
const params = {
  method: 'eth_getBlockByNumber',
  params: ['latest', false],
}
 const block = await fetchFromProvider(provider, params)

#### Parameters

| Name | Type | Description |
| :------ | :------ | :------ |
| `url` | `string` | the URL for the JSON RPC provider |
| `params` | `rpcParams` | the parameters for the JSON-RPC method - refer to https://ethereum.org/en/developers/docs/apis/json-rpc/ for details on RPC methods |

#### Returns

`Promise`<`any`\>

the `result` field from the JSON-RPC response

#### Defined in

[packages/util/src/provider.ts:23](https://github.com/ethereumjs/ethereumjs-monorepo/blob/master/packages/util/src/provider.ts#L23)

___

### formatBigDecimal

▸ **formatBigDecimal**(`numerator`, `denominator`, `maxDecimalFactor`): `string`

#### Parameters

| Name | Type |
| :------ | :------ |
| `numerator` | `bigint` |
| `denominator` | `bigint` |
| `maxDecimalFactor` | `bigint` |

#### Returns

`string`

#### Defined in

[packages/util/src/units.ts:5](https://github.com/ethereumjs/ethereumjs-monorepo/blob/master/packages/util/src/units.ts#L5)

___

### fromAscii

▸ **fromAscii**(`stringValue`): `string`

Should be called to get hex representation (prefixed by 0x) of ascii string

#### Parameters

| Name | Type |
| :------ | :------ |
| `stringValue` | `string` |

#### Returns

`string`

hex representation of input string

#### Defined in

[packages/util/src/internal.ts:152](https://github.com/ethereumjs/ethereumjs-monorepo/blob/master/packages/util/src/internal.ts#L152)

___

### fromRpcSig

▸ **fromRpcSig**(`sig`): [`ECDSASignature`](interfaces/ECDSASignature.md)

Convert signature format of the `eth_sign` RPC method to signature parameters

NOTE: For an extracted `v` value < 27 (see Geth bug https://github.com/ethereum/go-ethereum/issues/2053)
`v + 27` is returned for the `v` value
NOTE: After EIP1559, `v` could be `0` or `1` but this function assumes
it's a signed message (EIP-191 or EIP-712) adding `27` at the end. Remove if needed.

#### Parameters

| Name | Type |
| :------ | :------ |
| `sig` | `string` |

#### Returns

[`ECDSASignature`](interfaces/ECDSASignature.md)

#### Defined in

[packages/util/src/signature.ts:142](https://github.com/ethereumjs/ethereumjs-monorepo/blob/master/packages/util/src/signature.ts#L142)

___

### fromSigned

▸ **fromSigned**(`num`): `bigint`

Interprets a `Uint8Array` as a signed integer and returns a `BigInt`. Assumes 256-bit numbers.

#### Parameters

| Name | Type | Description |
| :------ | :------ | :------ |
| `num` | `Uint8Array` | Signed integer value |

#### Returns

`bigint`

#### Defined in

[packages/util/src/bytes.ts:329](https://github.com/ethereumjs/ethereumjs-monorepo/blob/master/packages/util/src/bytes.ts#L329)

___

### fromUtf8

▸ **fromUtf8**(`stringValue`): `string`

Should be called to get hex representation (prefixed by 0x) of utf8 string.
Strips leading and trailing 0's.

#### Parameters

| Name | Type |
| :------ | :------ |
| `stringValue` | `string` |

#### Returns

`string`

hex representation of input string

#### Defined in

[packages/util/src/internal.ts:139](https://github.com/ethereumjs/ethereumjs-monorepo/blob/master/packages/util/src/internal.ts#L139)

___

### generateAddress

▸ **generateAddress**(`from`, `nonce`): `Uint8Array`

Generates an address of a newly created contract.

#### Parameters

| Name | Type | Description |
| :------ | :------ | :------ |
| `from` | `Uint8Array` | The address which is creating this new address |
| `nonce` | `Uint8Array` | The nonce of the from account |

#### Returns

`Uint8Array`

#### Defined in

[packages/util/src/account.ts:207](https://github.com/ethereumjs/ethereumjs-monorepo/blob/master/packages/util/src/account.ts#L207)

___

### generateAddress2

▸ **generateAddress2**(`from`, `salt`, `initCode`): `Uint8Array`

Generates an address for a contract created using CREATE2.

#### Parameters

| Name | Type | Description |
| :------ | :------ | :------ |
| `from` | `Uint8Array` | The address which is creating this new address |
| `salt` | `Uint8Array` | A salt |
| `initCode` | `Uint8Array` | The init code of the contract being created |

#### Returns

`Uint8Array`

#### Defined in

[packages/util/src/account.ts:227](https://github.com/ethereumjs/ethereumjs-monorepo/blob/master/packages/util/src/account.ts#L227)

___

### getBinarySize

▸ **getBinarySize**(`str`): `number`

Get the binary size of a string

#### Parameters

| Name | Type |
| :------ | :------ |
| `str` | `string` |

#### Returns

`number`

the number of bytes contained within the string

#### Defined in

[packages/util/src/internal.ts:75](https://github.com/ethereumjs/ethereumjs-monorepo/blob/master/packages/util/src/internal.ts#L75)

___

### getBlobs

▸ **getBlobs**(`input`): `Uint8Array`[]

#### Parameters

| Name | Type |
| :------ | :------ |
| `input` | `string` |

#### Returns

`Uint8Array`[]

#### Defined in

[packages/util/src/blobs.ts:34](https://github.com/ethereumjs/ethereumjs-monorepo/blob/master/packages/util/src/blobs.ts#L34)

___

### getKeys

▸ **getKeys**(`params`, `key`, `allowEmpty?`): `string`[]

Returns the keys from an array of objects.

**`Example`**

```js
getKeys([{a: '1', b: '2'}, {a: '3', b: '4'}], 'a') => ['1', '3']

@param params @param key @param allowEmpty @returns output just a simple array of output keys

Parameters

Name	Type
params	Record<string, string>[]
key	string
allowEmpty?	boolean

Returns

string[]

Defined in

packages/util/src/internal.ts:174

---

getProvider

▸ getProvider(provider): string

Parameters

Name	Type	Description
provider	string | EthersProvider	a URL string or EthersProvider

Returns

string

the extracted URL string for the JSON-RPC Provider

Defined in

packages/util/src/provider.ts:63

---

hashPersonalMessage

▸ hashPersonalMessage(message): Uint8Array

Returns the keccak-256 hash of message, prefixed with the header used by the eth_sign RPC call. The output of this function can be fed into ecsign to produce the same signature as the eth_sign call for a given message, or fed to ecrecover along with a signature to recover the public key used to produce the signature.

Parameters

Name	Type
message	Uint8Array

Returns

Uint8Array

Defined in

packages/util/src/signature.ts:219

---

hexToBytes

▸ hexToBytes(hex): Uint8Array

Parameters

Name	Type
hex	string

Returns

Uint8Array

Defined in

packages/util/src/bytes.ts:110

---

importPublic

▸ importPublic(publicKey): Uint8Array

Converts a public key to the Ethereum format.

Parameters

Name	Type
publicKey	Uint8Array

Returns

Uint8Array

Defined in

packages/util/src/account.ts:326

---

initKZG

▸ initKZG(kzgLib, trustedSetupPath?): void

Parameters

Name	Type	Description
kzgLib	Kzg	a KZG implementation (defaults to c-kzg)
trustedSetupPath?	string	the full path (e.g. "/home/linux/devnet4.txt") to a kzg trusted setup text file

Returns

void

Defined in

packages/util/src/kzg.ts:38

---

int32ToBytes

▸ int32ToBytes(value, littleEndian?): Uint8Array

Notice

Convert a 32-bit integer to a Uint8Array.

Parameters

Name	Type	Default value	Description
value	number	undefined	The 32-bit integer to convert.
littleEndian	boolean	false	True for little-endian, undefined or false for big-endian.

Returns

Uint8Array

A Uint8Array of length 4 containing the integer.

Defined in

packages/util/src/bytes.ts:516

---

intToBytes

▸ intToBytes(i): Uint8Array

Converts an number to a Uint8Array

Parameters

Name	Type
i	number

Returns

Uint8Array

Defined in

packages/util/src/bytes.ts:146

---

intToHex

▸ intToHex(i): string

Converts a number into a PrefixedHexString

Parameters

Name	Type
i	number

Returns

string

Defined in

packages/util/src/bytes.ts:134

---

intToUnpaddedBytes

▸ intToUnpaddedBytes(value): Uint8Array

Convert value from number to an unpadded Uint8Array (useful for RLP transport)

Parameters

Name	Type	Description
value	number	the bigint to convert

Returns

Uint8Array

Defined in

packages/util/src/bytes.ts:433

---

isHexPrefixed

▸ isHexPrefixed(str): boolean

Returns a Boolean on whether or not the a String starts with '0x'

Throws

if the str input is not a string

Parameters

Name	Type	Description
str	string	the string input value

Returns

boolean

a boolean if it is or is not hex prefixed

Defined in

packages/util/src/internal.ts:33

---

isHexString

▸ isHexString(value, length?): boolean

Is the string a hex string.

Parameters

Name	Type
value	string
length?	number

Returns

boolean

output the string is a hex string

Defined in

packages/util/src/internal.ts:206

---

isValidAddress

▸ isValidAddress(hexAddress): boolean

Checks if the address is a valid. Accepts checksummed addresses too.

Parameters

Name	Type
hexAddress	string

Returns

boolean

Defined in

packages/util/src/account.ts:140

---

isValidChecksumAddress

▸ isValidChecksumAddress(hexAddress, eip1191ChainId?): boolean

Checks if the address is a valid checksummed address.

See toChecksumAddress' documentation for details about the eip1191ChainId parameter.

Parameters

Name	Type
hexAddress	string
eip1191ChainId?	BigIntLike

Returns

boolean

Defined in

packages/util/src/account.ts:195

---

isValidPrivate

▸ isValidPrivate(privateKey): boolean

Checks if the private key satisfies the rules of the curve secp256k1.

Parameters

Name	Type
privateKey	Uint8Array

Returns

boolean

Defined in

packages/util/src/account.ts:251

---

isValidPublic

▸ isValidPublic(publicKey, sanitize?): boolean

Checks if the public key satisfies the rules of the curve secp256k1 and the requirements of Ethereum.

Parameters

Name	Type	Default value	Description
publicKey	Uint8Array	undefined	The two points of an uncompressed key, unless sanitize is enabled
sanitize	boolean	false	Accept public keys in other formats

Returns

boolean

Defined in

packages/util/src/account.ts:261

---

isValidSignature

▸ isValidSignature(v, r, s, homesteadOrLater?, chainId?): boolean

Validate a ECDSA signature. NOTE: Accepts v === 0 | v === 1 for EIP1559 transactions

Parameters

Name	Type	Default value	Description
v	bigint	undefined	-
r	Uint8Array	undefined	-
s	Uint8Array	undefined	-
homesteadOrLater	boolean	true	Indicates whether this is being used on either the homestead hardfork or a later one
chainId?	bigint	undefined	-

Returns

boolean

Defined in

packages/util/src/signature.ts:179

---

isZeroAddress

▸ isZeroAddress(hexAddress): boolean

Checks if a given address is the zero address.

Parameters

Name	Type
hexAddress	string

Returns

boolean

Defined in

packages/util/src/account.ts:346

---

padToEven

▸ padToEven(value): string

Pads a String to have an even length

Parameters

Name	Type
value	string

Returns

string

output

Defined in

packages/util/src/internal.ts:58

---

parseGethGenesisState

▸ parseGethGenesisState(json): GenesisState

Parses the geth genesis state into Blockchain GenesisState

Parameters

Name	Type	Description
json	any	representing the alloc key in a Geth genesis file

Returns

GenesisState

Defined in

packages/util/src/genesis.ts:47

---

privateToAddress

▸ privateToAddress(privateKey): Uint8Array

Returns the ethereum address of a given private key.

Parameters

Name	Type	Description
privateKey	Uint8Array	A private key must be 256 bits wide

Returns

Uint8Array

Defined in

packages/util/src/account.ts:319

---

privateToPublic

▸ privateToPublic(privateKey): Uint8Array

Returns the ethereum public key of a given private key.

Parameters

Name	Type	Description
privateKey	Uint8Array	A private key must be 256 bits wide

Returns

Uint8Array

Defined in

packages/util/src/account.ts:309

---

pubToAddress

▸ pubToAddress(pubKey, sanitize?): Uint8Array

Returns the ethereum address of a given public key. Accepts "Ethereum public keys" and SEC1 encoded keys.

Parameters

Name	Type	Default value	Description
pubKey	Uint8Array	undefined	The two points of an uncompressed key, unless sanitize is enabled
sanitize	boolean	false	Accept public keys in other formats

Returns

Uint8Array

Defined in

packages/util/src/account.ts:292

---

publicToAddress

▸ publicToAddress(pubKey, sanitize?): Uint8Array

Returns the ethereum address of a given public key. Accepts "Ethereum public keys" and SEC1 encoded keys.

Parameters

Name	Type	Default value	Description
pubKey	Uint8Array	undefined	The two points of an uncompressed key, unless sanitize is enabled
sanitize	boolean	false	Accept public keys in other formats

Returns

Uint8Array

Defined in

packages/util/src/account.ts:292

---

randomBytes

▸ randomBytes(length): Uint8Array

Generates a Uint8Array of random bytes of specified length.

Parameters

Name	Type	Description
length	number	The length of the Uint8Array.

Returns

Uint8Array

A Uint8Array of random bytes of specified length.

Defined in

packages/util/src/bytes.ts:458

---

setLengthLeft

▸ setLengthLeft(msg, length): Uint8Array

Left Pads a Uint8Array with leading zeros till it has length bytes. Or it truncates the beginning if it exceeds.

Parameters

Name	Type	Description
msg	Uint8Array	the value to pad
length	number	the number of bytes the output should be

Returns

Uint8Array

Defined in

packages/util/src/bytes.ts:201

---

setLengthRight

▸ setLengthRight(msg, length): Uint8Array

Right Pads a Uint8Array with trailing zeros till it has length bytes. it truncates the end if it exceeds.

Parameters

Name	Type	Description
msg	Uint8Array	the value to pad
length	number	the number of bytes the output should be

Returns

Uint8Array

Defined in

packages/util/src/bytes.ts:213

---

short

▸ short(bytes, maxLength?): string

Shortens a string or Uint8Array's hex string representation to maxLength (default 50).

Examples:

Input: '657468657265756d000000000000000000000000000000000000000000000000' Output: '657468657265756d0000000000000000000000000000000000…'

Parameters

Name	Type	Default value
bytes	string | Uint8Array	undefined
maxLength	number	50

Returns

string

Defined in

packages/util/src/bytes.ts:366

---

stripHexPrefix

▸ stripHexPrefix(str): string

Removes '0x' from a given String if present

Parameters

Name	Type	Description
str	string	the string value

Returns

string

the string without 0x prefix

Defined in

packages/util/src/internal.ts:46

---

toAscii

▸ toAscii(hex): string

Should be called to get ascii from its hex representation

Parameters

Name	Type
hex	string

Returns

string

ascii string representation of hex value

Defined in

packages/util/src/internal.ts:116

---

toBytes

▸ toBytes(v): Uint8Array

Attempts to turn a value into a Uint8Array. Inputs supported: Buffer, Uint8Array, String (hex-prefixed), Number, null/undefined, BigInt and other objects with a toArray() or toBytes() method.

Parameters

Name	Type	Description
v	ToBytesInputTypes	the value

Returns

Uint8Array

Defined in

packages/util/src/bytes.ts:285

---

toChecksumAddress

▸ toChecksumAddress(hexAddress, eip1191ChainId?): string

Returns a checksummed address.

If an eip1191ChainId is provided, the chainId will be included in the checksum calculation. This has the effect of checksummed addresses for one chain having invalid checksums for others. For more details see EIP-1191.

WARNING: Checksums with and without the chainId will differ and the EIP-1191 checksum is not backwards compatible to the original widely adopted checksum format standard introduced in EIP-55, so this will break in existing applications. Usage of this EIP is therefore discouraged unless you have a very targeted use case.

Parameters

Name	Type
hexAddress	string
eip1191ChainId?	BigIntLike

Returns

string

Defined in

packages/util/src/account.ts:162

---

toCompactSig

▸ toCompactSig(v, r, s, chainId?): string

Convert signature parameters into the format of Compact Signature Representation (EIP-2098). NOTE: Accepts v === 0 | v === 1 for EIP1559 transactions

Parameters

Name	Type
v	bigint
r	Uint8Array
s	Uint8Array
chainId?	bigint

Returns

string

Signature

Defined in

packages/util/src/signature.ts:115

---

toRpcSig

▸ toRpcSig(v, r, s, chainId?): string

Convert signature parameters into the format of eth_sign RPC method. NOTE: Accepts v === 0 | v === 1 for EIP1559 transactions

Parameters

Name	Type
v	bigint
r	Uint8Array
s	Uint8Array
chainId?	bigint

Returns

string

Signature

Defined in

packages/util/src/signature.ts:94

---

toType

▸ toType<T>(input, outputType): null

Convert an input to a specified type. Input of null/undefined returns null/undefined regardless of the output type.

Type parameters

Name	Type
T	extends TypeOutput

Parameters

Name	Type	Description
input	null	value to convert
outputType	T	type to output

Returns

null

Defined in

packages/util/src/types.ts:62

▸ toType<T>(input, outputType): undefined

Type parameters

Name	Type
T	extends TypeOutput

Parameters

Name	Type
input	undefined
outputType	T

Returns

undefined

Defined in

packages/util/src/types.ts:63

▸ toType<T>(input, outputType): TypeOutputReturnType[T]

Type parameters

Name	Type
T	extends TypeOutput

Parameters

Name	Type
input	ToBytesInputTypes
outputType	T

Returns

TypeOutputReturnType[T]

Defined in

packages/util/src/types.ts:64

---

toUnsigned

▸ toUnsigned(num): Uint8Array

Converts a BigInt to an unsigned integer and returns it as a Uint8Array. Assumes 256-bit numbers.

Parameters

Name	Type
num	bigint

Returns

Uint8Array

Defined in

packages/util/src/bytes.ts:338

---

unpadArray

▸ unpadArray(a): number[]

Trims leading zeros from an Array (of numbers).

Parameters

Name	Type
a	number[]

Returns

number[]

Defined in

packages/util/src/bytes.ts:251

---

unpadBytes

▸ unpadBytes(a): Uint8Array

Trims leading zeros from a Uint8Array.

Parameters

Name	Type
a	Uint8Array

Returns

Uint8Array

Defined in

packages/util/src/bytes.ts:241

---

unpadHex

▸ unpadHex(a): string

Trims leading zeros from a PrefixedHexString.

Parameters

Name	Type
a	string

Returns

string

Defined in

packages/util/src/bytes.ts:261

---

unprefixedHexToBytes

▸ unprefixedHexToBytes(inp): Uint8Array

Deprecated

Parameters

Name	Type
inp	string

Returns

Uint8Array

Defined in

packages/util/src/bytes.ts:48

---

utf8ToBytes

▸ utf8ToBytes(str): Uint8Array

Example

utf8ToBytes('abc') // new Uint8Array([97, 98, 99])

Parameters

Name	Type
str	string

Returns

Uint8Array

Defined in

node_modules/@noble/hashes/utils.d.ts:21

---

validateNoLeadingZeroes

▸ validateNoLeadingZeroes(values): void

Checks provided Uint8Array for leading zeroes and throws if found.

Examples:

Valid values: 0x1, 0x, 0x01, 0x1234 Invalid values: 0x0, 0x00, 0x001, 0x0001

Note: This method is useful for validating that RLP encoded integers comply with the rule that all integer values encoded to RLP must be in the most compact form and contain no leading zero bytes

Throws

if any provided value is found to have leading zero bytes

Parameters

Name	Type	Description
values	Object	An object containing string keys and Uint8Array values

Returns

void

Defined in

packages/util/src/bytes.ts:388

---

zeroAddress

▸ zeroAddress(): string

Returns the zero address.

Returns

string

Defined in

packages/util/src/account.ts:337

---

zeros

▸ zeros(bytes): Uint8Array

Returns a Uint8Array filled with 0s.

Parameters

Name	Type	Description
bytes	number	the number of bytes of the Uint8Array

Returns

Uint8Array

Defined in

packages/util/src/bytes.ts:168