Approve

Get calldata for approve transaction and spender address
All requests and examples are made for Ethereum mainnet, if you plan to use the API for Binance Smart Chain, change the request url as follows: 
https://api.1inch.exchange/v3.0/56/<method>
get
Approve Calldata
https://api.1inch.exchange/v3.0/1/approve/calldata
Get a calldata for an approve transaction.
Request
Response
Request
Query Parameters
amount
optional
integer
Amount of tokens to be approved:
 0 — set approval to zero (lock a token)
>0 — approve exact amount of tokens.
infinity
optional
boolean
If set, approve infinite amount of tokens
tokenAddress
required
string
The contract address of a token

Response
200: OK
Success response
{
  "to": [
    "string"             // token contract address
  ],
  "value": "string",     // amount of eth to be sent (in wei)
  "gasPrice": "string",  // recommended gas price (in wei)
  "data": "string"       // result calldata
}
Do not combine amount parameter with infinity parameter, only one must be sent.
amount is set in minimal divisible units: for example, to unlock 1 DAI, amount should be 1000000000000000000, to unlock 1.03 USDC, amount should be 1030000.
Request url to unlock 5000 DAI tokens
https://api.1inch.exchange/v3.0/1/approve/calldata?amount=5000000000000000000000&tokenAddress=0x6b175474e89094c44da98b954eedeac495271d0f
curl
curl -X GET "https://api.1inch.exchange/v3.0/1/approve/calldata?amount=5000000000000000000000&tokenAddress=0x6b175474e89094c44da98b954eedeac495271d0f" -H "accept: application/json"
Response body
Response headers
Response body
{
  "data": "0x095ea7b3000000000000000000000000111111125434b319222cdbf8c261674adb56f3aeffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff",
  "gasPrice": "51000000000",
  "to": "0x6b175474e89094c44da98b954eedeac495271d0f",
  "value": "0"
}
Response headers
access-control-allow-origin: * 
 cache-control: public,max-age=300,s-maxage=300 
 cf-cache-status: EXPIRED 
 cf-ray: 5f4206653b48e69c-LHR 
 cf-request-id: 067d2253420000e69c3e176000000001 
 content-encoding: gzip 
 content-type: application/json; charset=utf-8 
 date: Wed,18 Nov 2020 13:26:45 GMT 
 etag: W/"ec-iBWHynvCWl7Z7aoQEOVh6S9MqaM" 
 expect-ct: max-age=604800,report-uri="https://report-uri.cloudflare.com/cdn-cgi/beacon/expect-ct" 
 server: cloudflare 
 status: 200 
 vary: Origin,Accept-Encoding 
 x-powered-by: Express 
Please, note some token contracts, like USDT, require to set approval back to zero, before increasing it. 
It is recommended to make an estimate of this transaction before sending it to the node.
Test your request in web interface:
https://api.1inch.exchange/swagger/ethereum/#/Approve/ApproveController_getCallData​
get
Approve Spender
https://api.1inch.exchange/v3.0/1/approve/spender
Get the address to which you need to approve before the swap transaction
Request
Response
Request
​
Response
200: OK
Success response
{
  "address": "string" // address of 1inch contract
}
Request url
https://api.1inch.exchange/v3.0/1/approve/spender
curl
curl -X GET "https://api.1inch.exchange/v3.0/1/approve/spender" -H  "accept: application/json"
Response body
Headers
Response body
{
  "address": "0x111111125434b319222cdbf8c261674adb56f3ae"
}
Headers
access-control-allow-origin: * 
 cache-control: public,max-age=300,s-maxage=300 
 cf-cache-status: REVALIDATED 
 cf-ray: 5f4d1eb46d9807aa-LHR 
 cf-request-id: 06841184c0000007aa76229000000001 
 content-encoding: gzip 
 content-type: application/json; charset=utf-8 
 date: Thu,19 Nov 2020 21:45:44 GMT 
 etag: W/"38-OVahTHEixCdKnQb1Zt3v5Gr5QvY" 
 expect-ct: max-age=604800,report-uri="https://report-uri.cloudflare.com/cdn-cgi/beacon/expect-ct" 
 server: cloudflare 
 status: 304 
 vary: Origin,Accept-Encoding 
 x-powered-by: Express 
Test your request in web interface:
https://api.1inch.exchange/swagger/ethereum/#/Approve/ApproveController_getSpender​
Introduction
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Last updated 1 month ago
Approve

getApprove Calldata

getApprove Spender

get
Approve Calldata

get
Approve Spender
