Skip to main content

Type Definitions

This page documents the core type definitions and interfaces used throughout the Uniswap SDK Core.

Core Types​

Currency​

Base interface for all currencies (tokens and native currencies).

interface Currency {
  readonly isNative: boolean
  readonly isToken: boolean
  readonly chainId: number
  readonly decimals: number
  readonly symbol?: string
  readonly name?: string
}

BigintIsh​

Union type for values that can be converted to BigInt.

type BigintIsh = JSBI | string | number

Used throughout the SDK for numeric inputs that need high precision.

Utility Types​

TradeType​

Enum for specifying trade direction:

enum TradeType {
  EXACT_INPUT,
  EXACT_OUTPUT
}

Rounding​

Enum for mathematical rounding modes:

enum Rounding {
  ROUND_DOWN,
  ROUND_HALF_UP,
  ROUND_UP
}

Chain Support​

ChainId​

Supported blockchain networks:

enum ChainId {
  MAINNET = 1,
  GOERLI = 5,
  SEPOLIA = 11155111,
  OPTIMISM = 10,
  OPTIMISM_GOERLI = 420,
  ARBITRUM_ONE = 42161,
  ARBITRUM_GOERLI = 421613,
  POLYGON = 137,
  POLYGON_MUMBAI = 80001,
  CELO = 42220,
  CELO_ALFAJORES = 44787,
  GNOSIS = 100,
  MOONBEAM = 1284,
  BNB = 56,
  AVALANCHE = 43114,
  BASE_GOERLI = 84531,
  BASE = 8453
}

Constants​

Key constants used throughout the SDK:

  • MaxUint256 - Maximum uint256 value
  • ZERO - BigInt zero value
  • ONE - BigInt one value
  • TWO - BigInt two value
  • THREE - BigInt three value

Usage Examples​

Working with Currencies​

import { Token, Ether } from '@uniswap/sdk-core'

// Native ETH
const ETH = Ether.onChain(1)

// ERC-20 Token
const USDC = new Token(
  1, // chainId
  '0xA0b86a33E6417c29C8F6e3b6E4E12A82aA4Ca8e9', // address
  6, // decimals
  'USDC', // symbol
  'USD Coin' // name
)

Working with Amounts​

import { CurrencyAmount } from '@uniswap/sdk-core'

const amount = CurrencyAmount.fromRawAmount(USDC, '1000000') // 1 USDC
const readable = amount.toSignificant(6) // "1.000000"

For more detailed usage, see the individual class documentation and the SDK Guides.

Edit this page