validateAndParseAddress

Validates an Ethereum address and returns the checksummed version.

Import

import { validateAndParseAddress, checkValidAddress } from '@uniswap/sdk-core-next'

Functions

`validateAndParseAddress(address)`

Validates an address and returns the checksummed (EIP-55) version.

function validateAndParseAddress(address: string): Address.Address

Parameters

Name	Type	Description
`address`	`string`	The hex address to validate

Returns

Address.Address - The checksummed address.

Throws

Error if the address is invalid.

`checkValidAddress(address)`

A lighter validation that only checks format (0x prefix, length, hex characters) without computing the checksum.

function checkValidAddress(address: string): Address.Address

Parameters

Name	Type	Description
`address`	`string`	The hex address to validate

Returns

Address.Address - The address as-is (not checksummed).

Throws

Error if the address format is invalid.

Example

import { validateAndParseAddress, checkValidAddress } from '@uniswap/sdk-core-next'
 
// Valid address - returns checksummed
const checksummed = validateAndParseAddress('0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48')
console.log(checksummed) // '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48'
 
// Already checksummed - returns same
const same = validateAndParseAddress('0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48')
console.log(same) // '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48'
 
// Invalid checksum - throws error
try {
  validateAndParseAddress('0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB49')
} catch (e) {
  console.log(e.message) // "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB49 is not a valid address."
}
 
// Light validation (no checksum verification)
const quick = checkValidAddress('0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48')
console.log(quick) // '0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48' (lowercase preserved)
 
// Invalid format - throws
try {
  checkValidAddress('0xinvalid')
} catch (e) {
  console.log(e.message) // "0xinvalid is not a valid address."
}

Validation Rules

`validateAndParseAddress`

Must be a valid hex string
Must be 42 characters (including 0x prefix)
Returns EIP-55 checksummed address
Validates checksum if mixed case

`checkValidAddress`

Must start with 0x (case insensitive)
Must be exactly 42 characters
Must contain only hex characters (0-9, a-f, A-F)
Does NOT validate or compute checksum

When to Use Each

// Use validateAndParseAddress for:
// - User input validation
// - Ensuring consistent address format
// - Security-critical operations
 
const userInput = '0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48'
const token = new Token(1, validateAndParseAddress(userInput), 6)
 
// Use checkValidAddress for:
// - Faster validation when checksum isn't critical
// - Processing large batches of addresses
// - When addresses come from trusted sources
 
const trustedAddress = '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48'
const quickCheck = checkValidAddress(trustedAddress)

EIP-55 Checksum

The checksum is encoded in the capitalization of the hex characters:

0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48
  ^                 ^      ^
  Capital A         Capital D    Capital E

This allows detecting typos in addresses. An address with incorrect capitalization will fail validation.