# Swap & Cross-Chain ## Swap ### Estimation This endpoint retrieves a list of decentralized exchanges (dexes) where the selected pair can be swapped. The list is sorted by profit, so we recommend choosing the first dex in the list. ``` curl -X 'GET' 'https://api.crowdswap.org/api/v1/swap/estimate-all?fromToken%5Baddress%5D=0x0000000000000000000000000000000000001010&fromToken%5BchainId%5D=137&fromToken%5Bdecimals%5D=18&fromToken%5Bname%5D=Matic%20Token&fromToken%5Bsymbol%5D=MATIC&toToken%5Baddress%5D=0x483dd3425278C1f79F377f1034d9d2CaE55648B6&toToken%5BchainId%5D=137&toToken%5Bdecimals%5D=18&toToken%5Bname%5D=Crowd%20Token&toToken%5Bsymbol%5D=CROWD&amount=1000000000000000000' \ -H 'accept: application/json' -H 'x-api-key: YOUR_API_KEY' ``` #### Request | Field | Description | Example | | -------------------- | --------------------------------------------------------------------------------------------------- | ------------------------------------------ | | fromToken\[address] | Address of source token | 0x0000000000000000000000000000000000001010 | | fromToken\[chainId] | Chain id of source token | 137 | | fromToken\[decimals] | Decimals of source token | 18 | | fromToken\[name] | Name of source token | Matic Token | | fromToken\[symbol] | Symbol of source token | MATIC | | toToken\[address] | Address of destination token | 0x483dd3425278C1f79F377f1034d9d2CaE55648B6 | | toToken\[chainId] | Chain id of destination token | 137 | | toToken\[decimals] | Decimals of destination token | 18 | | toToken\[name] | Name of destination token | Crowd Token | | toToken\[symbol] | Symbol of destination token | CROWD | | amount | An amount of the source token to be swapped (The decimal of token must be considered in the amount) | 1000000000000000000 | #### Response ``` {​ "successfulEstimationsList": [​ {​ "swapName": "string",​ "delegatedDex": "string",​ "fromToken": "string",​ "fromTokenPrice": "string",​ "toToken": "string",​ "toTokenPrice": "string",​ "amountIn": "string",​ "amountOut": "string",​ "minAmountOut": "string",​ "route": "string",​ "reserves": [​ "string"​ ],​ "priceImpact": "string",​ "poolInfo": "string",​ "swapFee": "string",​ "networkFee": "string",​ "gasPrice": "string",​ "currentDexFeePercentage": "string",​ "crowdswapFeePercentage": "string",​ "swapFeeInUSDT": "string",​ "networkFeeInUSDT": "string",​ "crowdswapFeeInUSDT": "string",​ "totalFeeInUSDT": "string",​ "pricePerToken": "number",​ "cost": "number",​ "totalPaidInUSDT": "string",​ "totalIncomeInUSDT": "string",​ "amountOutInUSDT": "string",​ "amountInInUSDT": "string",​ "amountOutPerAmountInRatio": "string",​ "amountInPerAmountOutRatio": "string",​ "approveAddress": "string",​ "tradeType": "number",​ "trade": {}​ }​ ]​ ​} ``` ### Transaction This endpoint returns `from`, `to`, `data`, `value`, and `gasLimit`, all of which needed for executing a swap. * A dex name must be added to the url. The dex name can be found in estimation response e.g., CrowdSwapV2, Quickswap ``` curl -X 'GET' \ 'https://api.crowdswap.org/api/v1/swap/{dex}?fromToken%5Baddress%5D=0x0000000000000000000000000000000000001010&fromToken%5BchainId%5D=137&fromToken%5Bdecimals%5D=18&fromToken%5Bname%5D=Matic%20Token&fromToken%5Bsymbol%5D=MATIC&toToken%5Baddress%5D=0x483dd3425278C1f79F377f1034d9d2CaE55648B6&toToken%5BchainId%5D=137&toToken%5Bdecimals%5D=18&toToken%5Bname%5D=Crowd%20Token&toToken%5Bsymbol%5D=CROWD&amount=1000000000000000000&userAddress=0x000000000000000000000000000000000000000&receiverAddress=0x000000000000000000000000000000000000000' \ -H 'accept: application/json' -H 'x-api-key: YOUR_API_KEY' ``` #### Request | Field | Description | Example | | -------------------- | ---------------------------------------------------------------------------------------- | ------------------------------------------ | | fromToken\[address] | Address of source token | 0x0000000000000000000000000000000000001010 | | fromToken\[chainId] | Chain id of source token | 137 | | fromToken\[decimals] | Decimals of source token | 18 | | fromToken\[name] | Name of source token | Matic Token | | fromToken\[symbol] | Symbol of source token | MATIC | | toToken\[address] | Address of destination token | 0x483dd3425278C1f79F377f1034d9d2CaE55648B6 | | toToken\[chainId] | Chain id of destination token | 137 | | toToken\[decimals] | Decimals of destination token | 18 | | toToken\[name] | Name of destination token | Crowd Token | | toToken\[symbol] | Symbol of destination token | CROWD | | amount | An amount of input tokens to swap (the entrance amount must be based on token's decimal) | 1000000000000000000 | | userAddress | Address of the user who initiates the swap transaction | any arbitrary address | | receiverAddress | Address of the recipient if it is different from the userAddress | any arbitrary address | #### Response ``` { "from": "string", "to": "string", "data": "string", "value": "string", "gasLimit": "string" } ``` ## Cross-Chain ### Estimation and Transaction This endpoint finds a route with potentially the best possible outcome for the requested cross-chain pair and returns an estimation. ``` curl -X 'GET' \ 'https://api.crowdswap.org/api/v1/crossChainSwap/estimate-all?fromToken%5Baddress%5D=0x0000000000000000000000000000000000001010&fromToken%5BchainId%5D=137&fromToken%5Bdecimals%5D=18&fromToken%5Bname%5D=Matic%20Token&fromToken%5Bsymbol%5D=MATIC&toToken%5Baddress%5D=0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE&toToken%5BchainId%5D=56&toToken%5Bdecimals%5D=18&toToken%5Bname%5D=Binance%20Coin&toToken%5Bsymbol%5D=BNB&amountIn=1000000000000000000' \ -H 'accept: application/json' -H 'x-api-key: YOUR_API_KEY' ``` #### Request | Field | Description | Example | | -------------------- | ---------------------------------------------------------------------------------------------- | ------------------------------------------ | | fromToken\[address] | Address of source token | 0x0000000000000000000000000000000000001010 | | fromToken\[chainId] | Chain id of source token | 137 | | fromToken\[decimals] | Decimals of source token | 18 | | fromToken\[name] | Name of source token | Matic Token | | fromToken\[symbol] | Symbol of source token | MATIC | | toToken\[address] | Address of destination token | 0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE | | toToken\[chainId] | Chain id of destination token | 56 | | toToken\[decimals] | Decimals of destination token | 18 | | toToken\[name] | Name of destination token | Binance Coin | | toToken\[symbol] | Symbol of destination token | BNB | | amountIn | An amount of `fromToken` to be swapped (The decimal of token must be considered in the amount) | 1000000000000000000 | | userAddress | Address of the user who initiates the cross-chain swap transaction | any arbitrary address | #### Response ``` { "crossChainName": "string", "tokenIn": { "address": "string", "chainId": "number", "decimals": "number", "amount": "string", "symbol": "string" }, "tokenOut": { "address": "string", "chainId": "number", "decimals": "number", "amount": "string", "symbol": "string" }, "amountIn": "string", "amountOut": "string", "minAmountOut": "string", "approveAddress": "string", "status": "number", "msg": "string", "swapTx": { "to": "string", "data": "number", "value": "number", "gasLimit": "string" }, "fees": { "token": { "address": "string", "chainId": "number", "decimals": "number", "name": "string", "symbol": "string" }, "amount": "string", "type": "number" }, "includedInOutputFees": { "token": { "address": "string", "chainId": "number", "decimals": "number", "name": "string", "symbol": "string" }, "amount": "string", "type": "number" }, "swapSpecData": {} } ``` ## How to send a transaction Both `Swap` and `Cross-Chain` APIs return the data needed for executing a transaction. The data, which named `tx` in below code, contains `from (user address)`, `to (contract address)`, `data (populated data)`, `value (coin value if needed)`, `gasLimit`. You can use below code to run your transaction. To send a transaction, you can get `tx` from the response of Swap and Cross-Chain end-points. ```javascript import { ExternalProvider, Web3Provider } from '@ethersproject/providers'; export class TransactionService{ private provider?: Web3Provider; constructor(){ this.provider = new Web3Provider(provider as ExternalProvider, 'any'); } function sendTransaction(tx){ this.provider?.getSigner().sendTransaction(tx); } } ``` --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.crowdswap.org/developers/swap_api.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.