Router02

Because routers are stateless and do not hold token balances, they can be replaced safely and trustlessly, if necessary. This may happen if more efficient smart contract patterns are discovered, or if additional functionality is desired. For this reason, routers have release numbers, starting at 01. This is currently recommended release, 02.
Code
​UniswapV2Router02.sol​
Address
UniswapV2Router02 is deployed at 0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D on the Ethereum mainnet, and the Ropsten, Rinkeby, Görli, and Kovan testnets. It was built from commit 6961711.
Read-Only Functions
factory​​
function factory() external pure returns (address);
Copy
Returns factory address.
WETH​​
function WETH() external pure returns (address);
Copy
Returns the canonical WETH address on the Ethereum mainnet, or the Ropsten, Rinkeby, Görli, or Kovan testnets.
quote​​
See quote.
getAmountOut​​
See getAmountOut.
getAmountIn​​
See getAmountIn.
getAmountsOut​​
function getAmountsOut(uint amountIn, address[] memory path) public view returns (uint[] memory amounts);
Copy
See getAmountsOut.
getAmountsIn​​
function getAmountsIn(uint amountOut, address[] memory path) public view returns (uint[] memory amounts);
Copy
See getAmountsIn.
State-Changing Functions
addLiquidity​​
function addLiquidity(  address tokenA,  address tokenB,  uint amountADesired,  uint amountBDesired,  uint amountAMin,  uint amountBMin,  address to,  uint deadline) external returns (uint amountA, uint amountB, uint liquidity);
Copy
Adds liquidity to an ERC-20⇄ERC-20 pool.
To cover all possible scenarios, msg.sender should have already given the router an allowance of at least amountADesired/amountBDesired on tokenA/tokenB.
Always adds assets at the ideal ratio, according to the price when the transaction is executed.
If a pool for the passed tokens does not exists, one is created automatically, and exactly amountADesired/amountBDesired tokens are added.
Name
Type
Text
tokenA
address
A pool token.
tokenB
address
A pool token.
amountADesired
uint
The amount of tokenA to add as liquidity if the B/A price is <= amountBDesired/amountADesired (A depreciates).
amountBDesired
uint
The amount of tokenB to add as liquidity if the A/B price is <= amountADesired/amountBDesired (B depreciates).
amountAMin
uint
Bounds the extent to which the B/A price can go up before the transaction reverts. Must be <= amountADesired.
amountBMin
uint
Bounds the extent to which the A/B price can go up before the transaction reverts. Must be <= amountBDesired.
to
address
Recipient of the liquidity tokens.
deadline
uint
Unix timestamp after which the transaction will revert.
​
​
​
amountA
uint
The amount of tokenA sent to the pool.
amountB
uint
The amount of tokenB sent to the pool.
liquidity
uint
The amount of liquidity tokens minted.
addLiquidityETH​​
function addLiquidityETH(  address token,  uint amountTokenDesired,  uint amountTokenMin,  uint amountETHMin,  address to,  uint deadline) external payable returns (uint amountToken, uint amountETH, uint liquidity);
Copy
Adds liquidity to an ERC-20⇄WETH pool with ETH.
To cover all possible scenarios, msg.sender should have already given the router an allowance of at least amountTokenDesired on token.
Always adds assets at the ideal ratio, according to the price when the transaction is executed.
msg.value is treated as a amountETHDesired.
Leftover ETH, if any, is returned to msg.sender.
If a pool for the passed token and WETH does not exists, one is created automatically, and exactly amountTokenDesired/msg.value tokens are added.
Name
Type
Text
token
address
A pool token.
amountTokenDesired
uint
The amount of token to add as liquidity if the WETH/token price is <= msg.value/amountTokenDesired (token depreciates).
msg.value (amountETHDesired)
uint
The amount of ETH to add as liquidity if the token/WETH price is <= amountTokenDesired/msg.value (WETH depreciates).
amountTokenMin
uint
Bounds the extent to which the WETH/token price can go up before the transaction reverts. Must be <= amountTokenDesired.
amountETHMin
uint
Bounds the extent to which the token/WETH price can go up before the transaction reverts. Must be <= msg.value.
to
address
Recipient of the liquidity tokens.
deadline
uint
Unix timestamp after which the transaction will revert.
​
​
​
amountToken
uint
The amount of token sent to the pool.
amountETH
uint
The amount of ETH converted to WETH and sent to the pool.
liquidity
uint
The amount of liquidity tokens minted.
removeLiquidity​​
function removeLiquidity(  address tokenA,  address tokenB,  uint liquidity,  uint amountAMin,  uint amountBMin,  address to,  uint deadline) external returns (uint amountA, uint amountB);
Copy
Removes liquidity from an ERC-20⇄ERC-20 pool.
msg.sender should have already given the router an allowance of at least liquidity on the pool.
Name
Type
Text
tokenA
address
A pool token.
tokenB
address
A pool token.
liquidity
uint
The amount of liquidity tokens to remove.
amountAMin
uint
The minimum amount of tokenA that must be received for the transaction not to revert.
amountBMin
uint
The minimum amount of tokenB that must be received for the transaction not to revert.
to
address
Recipient of the underlying assets.
deadline
uint
Unix timestamp after which the transaction will revert.
​
​
​
amountA
uint
The amount of tokenA received.
amountB
uint
The amount of tokenB received.
removeLiquidityETH​​
function removeLiquidityETH(  address token,  uint liquidity,  uint amountTokenMin,  uint amountETHMin,  address to,  uint deadline) external returns (uint amountToken, uint amountETH);
Copy
Removes liquidity from an ERC-20⇄WETH pool and receive ETH.
msg.sender should have already given the router an allowance of at least liquidity on the pool.
Name
Type
Text
token
address
A pool token.
liquidity
uint
The amount of liquidity tokens to remove.
amountTokenMin
uint
The minimum amount of token that must be received for the transaction not to revert.
amountETHMin
uint
The minimum amount of ETH that must be received for the transaction not to revert.
to
address
Recipient of the underlying assets.
deadline
uint
Unix timestamp after which the transaction will revert.
​
​
​
amountToken
uint
The amount of token received.
amountETH
uint
The amount of ETH received.
removeLiquidityWithPermit​​
function removeLiquidityWithPermit(  address tokenA,  address tokenB,  uint liquidity,  uint amountAMin,  uint amountBMin,  address to,  uint deadline,  bool approveMax, uint8 v, bytes32 r, bytes32 s) external returns (uint amountA, uint amountB);
Copy
Removes liquidity from an ERC-20⇄ERC-20 pool without pre-approval, thanks to permit.
Name
Type
Text
tokenA
address
A pool token.
tokenB
address
A pool token.
liquidity
uint
The amount of liquidity tokens to remove.
amountAMin
uint
The minimum amount of tokenA that must be received for the transaction not to revert.
amountBMin
uint
The minimum amount of tokenB that must be received for the transaction not to revert.
to
address
Recipient of the underlying assets.
deadline
uint
Unix timestamp after which the transaction will revert.
approveMax
bool
Whether or not the approval amount in the signature is for liquidity or uint(-1).
v
uint8
The v component of the permit signature.
r
bytes32
The r component of the permit signature.
s
bytes32
The s component of the permit signature.
​
​
​
amountA
uint
The amount of tokenA received.
amountB
uint
The amount of tokenB received.
removeLiquidityETHWithPermit​​
function removeLiquidityETHWithPermit(  address token,  uint liquidity,  uint amountTokenMin,  uint amountETHMin,  address to,  uint deadline,  bool approveMax, uint8 v, bytes32 r, bytes32 s) external returns (uint amountToken, uint amountETH);
Copy
Removes liquidity from an ERC-20⇄WETTH pool and receive ETH without pre-approval, thanks to permit.
Name
Type
Text
token
address
A pool token.
liquidity
uint
The amount of liquidity tokens to remove.
amountTokenMin
uint
The minimum amount of token that must be received for the transaction not to revert.
amountETHMin
uint
The minimum amount of ETH that must be received for the transaction not to revert.
to
address
Recipient of the underlying assets.
deadline
uint
Unix timestamp after which the transaction will revert.
approveMax
bool
Whether or not the approval amount in the signature is for liquidity or uint(-1).
v
uint8
The v component of the permit signature.
r
bytes32
The r component of the permit signature.
s
bytes32
The s component of the permit signature.
​
​
​
amountToken
uint
The amount of token received.
amountETH
uint
The amount of ETH received.
removeLiquidityETHSupportingFeeOnTransferTokens​​
function removeLiquidityETHSupportingFeeOnTransferTokens(  address token,  uint liquidity,  uint amountTokenMin,  uint amountETHMin,  address to,  uint deadline) external returns (uint amountETH);
Copy
Identical to removeLiquidityETH, but succeeds for tokens that take a fee on transfer.
msg.sender should have already given the router an allowance of at least liquidity on the pool.
Name
Type
Text
token
address
A pool token.
liquidity
uint
The amount of liquidity tokens to remove.
amountTokenMin
uint
The minimum amount of token that must be received for the transaction not to revert.
amountETHMin
uint
The minimum amount of ETH that must be received for the transaction not to revert.
to
address
Recipient of the underlying assets.
deadline
uint
Unix timestamp after which the transaction will revert.
​
​
​
amountETH
uint
The amount of ETH received.
removeLiquidityETHWithPermitSupportingFeeOnTransferTokens​​
function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(  address token,  uint liquidity,  uint amountTokenMin,  uint amountETHMin,  address to,  uint deadline,  bool approveMax, uint8 v, bytes32 r, bytes32 s) external returns (uint amountETH);
Copy
Identical to removeLiquidityETHWithPermit, but succeeds for tokens that take a fee on transfer.
Name
Type
Text
token
address
A pool token.
liquidity
uint
The amount of liquidity tokens to remove.
amountTokenMin
uint
The minimum amount of token that must be received for the transaction not to revert.
amountETHMin
uint
The minimum amount of ETH that must be received for the transaction not to revert.
to
address
Recipient of the underlying assets.
deadline
uint
Unix timestamp after which the transaction will revert.
approveMax
bool
Whether or not the approval amount in the signature is for liquidity or uint(-1).
v
uint8
The v component of the permit signature.
r
bytes32
The r component of the permit signature.
s
bytes32
The s component of the permit signature.
​
​
​
amountETH
uint
The amount of ETH received.
swapExactTokensForTokens​​
function swapExactTokensForTokens(  uint amountIn,  uint amountOutMin,  address[] calldata path,  address to,  uint deadline) external returns (uint[] memory amounts);
Copy
Swaps an exact amount of input tokens for as many output tokens as possible, along the route determined by the path. The first element of path is the input token, the last is the output token, and any intermediate elements represent intermediate pairs to trade through (if, for example, a direct pair does not exist).
msg.sender should have already given the router an allowance of at least amountIn on the input token.
Name
Type
Text
amountIn
uint
The amount of input tokens to send.
amountOutMin
uint
The minimum amount of output tokens that must be received for the transaction not to revert.
path
address[] calldata
An array of token addresses. path.length must be >= 2. Pools for each consecutive pair of addresses must exist and have liquidity.
to
address
Recipient of the output tokens.
deadline
uint
Unix timestamp after which the transaction will revert.
​
​
​
amounts
uint[] memory
The input token amount and all subsequent output token amounts.
swapTokensForExactTokens​​
function swapTokensForExactTokens(  uint amountOut,  uint amountInMax,  address[] calldata path,  address to,  uint deadline) external returns (uint[] memory amounts);
Copy
Receive an exact amount of output tokens for as few input tokens as possible, along the route determined by the path. The first element of path is the input token, the last is the output token, and any intermediate elements represent intermediate tokens to trade through (if, for example, a direct pair does not exist).
msg.sender should have already given the router an allowance of at least amountInMax on the input token.
Name
Type
Text
amountOut
uint
The amount of output tokens to receive.
amountInMax
uint
The maximum amount of input tokens that can be required before the transaction reverts.
path
address[] calldata
An array of token addresses. path.length must be >= 2. Pools for each consecutive pair of addresses must exist and have liquidity.
to
address
Recipient of the output tokens.
deadline
uint
Unix timestamp after which the transaction will revert.
​
​
​
amounts
uint[] memory
The input token amount and all subsequent output token amounts.
swapExactETHForTokens​​
function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)  external  payable  returns (uint[] memory amounts);
Copy
Swaps an exact amount of ETH for as many output tokens as possible, along the route determined by the path. The first element of path must be WETH, the last is the output token, and any intermediate elements represent intermediate pairs to trade through (if, for example, a direct pair does not exist).
Name
Type
Text
msg.value (amountIn)
uint
The amount of ETH to send.
amountOutMin
uint
The minimum amount of output tokens that must be received for the transaction not to revert.
path
address[] calldata
An array of token addresses. path.length must be >= 2. Pools for each consecutive pair of addresses must exist and have liquidity.
to
address
Recipient of the output tokens.
deadline
uint
Unix timestamp after which the transaction will revert.
​
​
​
amounts
uint[] memory
The input token amount and all subsequent output token amounts.
swapTokensForExactETH​​
function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)  external  returns (uint[] memory amounts);
Copy
Receive an exact amount of ETH for as few input tokens as possible, along the route determined by the path. The first element of path is the input token, the last must be WETH, and any intermediate elements represent intermediate pairs to trade through (if, for example, a direct pair does not exist).
msg.sender should have already given the router an allowance of at least amountInMax on the input token.
If the to address is a smart contract, it must have the ability to receive ETH.
Name
Type
Text
amountOut
uint
The amount of ETH to receive.
amountInMax
uint
The maximum amount of input tokens that can be required before the transaction reverts.
path
address[] calldata
An array of token addresses. path.length must be >= 2. Pools for each consecutive pair of addresses must exist and have liquidity.
to
address
Recipient of ETH.
deadline
uint
Unix timestamp after which the transaction will revert.
​
​
​
amounts
uint[] memory
The input token amount and all subsequent output token amounts.
swapExactTokensForETH​​
function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)  external  returns (uint[] memory amounts);
Copy
Swaps an exact amount of tokens for as much ETH as possible, along the route determined by the path. The first element of path is the input token, the last must be WETH, and any intermediate elements represent intermediate pairs to trade through (if, for example, a direct pair does not exist).
If the to address is a smart contract, it must have the ability to receive ETH.
Name
Type
Text
amountIn
uint
The amount of input tokens to send.
amountOutMin
uint
The minimum amount of output tokens that must be received for the transaction not to revert.
path
address[] calldata
An array of token addresses. path.length must be >= 2. Pools for each consecutive pair of addresses must exist and have liquidity.
to
address
Recipient of the ETH.
deadline
uint
Unix timestamp after which the transaction will revert.
​
​
​
amounts
uint[] memory
The input token amount and all subsequent output token amounts.
swapETHForExactTokens​​
function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)  external  payable  returns (uint[] memory amounts);
Copy
Receive an exact amount of tokens for as little ETH as possible, along the route determined by the path. The first element of path must be WETH, the last is the output token and any intermediate elements represent intermediate pairs to trade through (if, for example, a direct pair does not exist).
Leftover ETH, if any, is returned to msg.sender.
Name
Type
Text
amountOut
uint
The amount of tokens to receive.
msg.value (amountInMax)
uint
The maximum amount of ETH that can be required before the transaction reverts.
path
address[] calldata
An array of token addresses. path.length must be >= 2. Pools for each consecutive pair of addresses must exist and have liquidity.
to
address
Recipient of the output tokens.
deadline
uint
Unix timestamp after which the transaction will revert.
​
​
​
amounts
uint[] memory
The input token amount and all subsequent output token amounts.
swapExactTokensForTokensSupportingFeeOnTransferTokens​​
function swapExactTokensForTokensSupportingFeeOnTransferTokens(  uint amountIn,  uint amountOutMin,  address[] calldata path,  address to,  uint deadline) external;
Copy
Identical to swapExactTokensForTokens, but succeeds for tokens that take a fee on transfer.
msg.sender should have already given the router an allowance of at least amountIn on the input token.
Name
Type
Text
amountIn
uint
The amount of input tokens to send.
amountOutMin
uint
The minimum amount of output tokens that must be received for the transaction not to revert.
path
address[] calldata
An array of token addresses. path.length must be >= 2. Pools for each consecutive pair of addresses must exist and have liquidity.
to
address
Recipient of the output tokens.
deadline
uint
Unix timestamp after which the transaction will revert.
swapExactETHForTokensSupportingFeeOnTransferTokens​​
function swapExactETHForTokensSupportingFeeOnTransferTokens(  uint amountOutMin,  address[] calldata path,  address to,  uint deadline) external payable;
Copy
Identical to swapExactETHForTokens, but succeeds for tokens that take a fee on transfer.
Name
Type
Text
msg.value (amountIn)
uint
The amount of ETH to send.
amountOutMin
uint
The minimum amount of output tokens that must be received for the transaction not to revert.
path
address[] calldata
An array of token addresses. path.length must be >= 2. Pools for each consecutive pair of addresses must exist and have liquidity.
to
address
Recipient of the output tokens.
deadline
uint
Unix timestamp after which the transaction will revert.
swapExactTokensForETHSupportingFeeOnTransferTokens​​
function swapExactTokensForETHSupportingFeeOnTransferTokens(  uint amountIn,  uint amountOutMin,  address[] calldata path,  address to,  uint deadline) external;
Copy
Identical to swapExactTokensForETH, but succeeds for tokens that take a fee on transfer.

Name	Type	Text
tokenA	`address`	A pool token.
tokenB	`address`	A pool token.
amountADesired	`uint`	The amount of tokenA to add as liquidity if the B/A price is <= amountBDesired/amountADesired (A depreciates).
amountBDesired	`uint`	The amount of tokenB to add as liquidity if the A/B price is <= amountADesired/amountBDesired (B depreciates).
amountAMin	`uint`	Bounds the extent to which the B/A price can go up before the transaction reverts. Must be <= amountADesired.
amountBMin	`uint`	Bounds the extent to which the A/B price can go up before the transaction reverts. Must be <= amountBDesired.
to	`address`	Recipient of the liquidity tokens.
deadline	`uint`	Unix timestamp after which the transaction will revert.

amountA	`uint`	The amount of tokenA sent to the pool.
amountB	`uint`	The amount of tokenB sent to the pool.
liquidity	`uint`	The amount of liquidity tokens minted.

Name	Type	Text
token	`address`	A pool token.
amountTokenDesired	`uint`	The amount of token to add as liquidity if the WETH/token price is <= `msg.value`/amountTokenDesired (token depreciates).
`msg.value` (amountETHDesired)	`uint`	The amount of ETH to add as liquidity if the token/WETH price is <= amountTokenDesired/`msg.value` (WETH depreciates).
amountTokenMin	`uint`	Bounds the extent to which the WETH/token price can go up before the transaction reverts. Must be <= amountTokenDesired.
amountETHMin	`uint`	Bounds the extent to which the token/WETH price can go up before the transaction reverts. Must be <= `msg.value`.
to	`address`	Recipient of the liquidity tokens.
deadline	`uint`	Unix timestamp after which the transaction will revert.

amountToken	`uint`	The amount of token sent to the pool.
amountETH	`uint`	The amount of ETH converted to WETH and sent to the pool.
liquidity	`uint`	The amount of liquidity tokens minted.

Name	Type	Text
amountIn	`uint`	The amount of input tokens to send.
amountOutMin	`uint`	The minimum amount of output tokens that must be received for the transaction not to revert.
path	`address[] calldata`	An array of token addresses. `path.length` must be >= 2. Pools for each consecutive pair of addresses must exist and have liquidity.
to	`address`	Recipient of the output tokens.
deadline	`uint`	Unix timestamp after which the transaction will revert.

amounts	`uint[] memory`	The input token amount and all subsequent output token amounts.

Name	Type	Text
amountOut	`uint`	The amount of output tokens to receive.
amountInMax	`uint`	The maximum amount of input tokens that can be required before the transaction reverts.
path	`address[] calldata`	An array of token addresses. `path.length` must be >= 2. Pools for each consecutive pair of addresses must exist and have liquidity.
to	`address`	Recipient of the output tokens.
deadline	`uint`	Unix timestamp after which the transaction will revert.

amounts	`uint[] memory`	The input token amount and all subsequent output token amounts.

Name	Type	Text
`msg.value` (amountIn)	`uint`	The amount of ETH to send.
amountOutMin	`uint`	The minimum amount of output tokens that must be received for the transaction not to revert.
path	`address[] calldata`	An array of token addresses. `path.length` must be >= 2. Pools for each consecutive pair of addresses must exist and have liquidity.
to	`address`	Recipient of the output tokens.
deadline	`uint`	Unix timestamp after which the transaction will revert.

amounts	`uint[] memory`	The input token amount and all subsequent output token amounts.

Name	Type	Text
amountOut	`uint`	The amount of ETH to receive.
amountInMax	`uint`	The maximum amount of input tokens that can be required before the transaction reverts.
path	`address[] calldata`	An array of token addresses. `path.length` must be >= 2. Pools for each consecutive pair of addresses must exist and have liquidity.
to	`address`	Recipient of ETH.
deadline	`uint`	Unix timestamp after which the transaction will revert.

amounts	`uint[] memory`	The input token amount and all subsequent output token amounts.

Name	Type	Text
amountOut	`uint`	The amount of tokens to receive.
`msg.value` (amountInMax)	`uint`	The maximum amount of ETH that can be required before the transaction reverts.
path	`address[] calldata`	An array of token addresses. `path.length` must be >= 2. Pools for each consecutive pair of addresses must exist and have liquidity.
to	`address`	Recipient of the output tokens.
deadline	`uint`	Unix timestamp after which the transaction will revert.

amounts	`uint[] memory`	The input token amount and all subsequent output token amounts.

Router02

Code

Address

Read-Only Functions

factory​​

WETH​​

quote​​

getAmountOut​​

getAmountIn​​

getAmountsOut​​

getAmountsIn​​

State-Changing Functions

addLiquidity​​

addLiquidityETH​​

removeLiquidity​​

removeLiquidityETH​​

removeLiquidityWithPermit​​

removeLiquidityETHWithPermit​​

removeLiquidityETHSupportingFeeOnTransferTokens​​

removeLiquidityETHWithPermitSupportingFeeOnTransferTokens​​

swapExactTokensForTokens​​

swapTokensForExactTokens​​

swapExactETHForTokens​​

swapTokensForExactETH​​

swapExactTokensForETH​​

swapETHForExactTokens​​

swapExactTokensForTokensSupportingFeeOnTransferTokens​​

swapExactETHForTokensSupportingFeeOnTransferTokens​​

swapExactTokensForETHSupportingFeeOnTransferTokens​​

factory

WETH

quote

getAmountOut

getAmountIn

getAmountsOut

getAmountsIn

addLiquidity

addLiquidityETH

removeLiquidity

removeLiquidityETH

removeLiquidityWithPermit

removeLiquidityETHWithPermit

removeLiquidityETHSupportingFeeOnTransferTokens

removeLiquidityETHWithPermitSupportingFeeOnTransferTokens

swapExactTokensForTokens

swapTokensForExactTokens

swapExactETHForTokens

swapTokensForExactETH

swapExactTokensForETH

swapETHForExactTokens

swapExactTokensForTokensSupportingFeeOnTransferTokens

swapExactETHForTokensSupportingFeeOnTransferTokens

swapExactTokensForETHSupportingFeeOnTransferTokens