--- updatedAt: 2026-06-09T12:06:23.000Z --- Fetch the complete documentation index at: https://docs.blockdaemon.com/llms.txt. Use this file to discover all available pages before exploring further. Append .md to any documentation page URL to get its markdown version. # Execute a Same Chain Swap This guide walks you through fetching a quote, checking token allowance, generating transactions, signing, and broadcasting them using **expand.network by Blockdaemon DeFi API**.

*** ## Step 1: Check the Swap Quote To begin a token swap, retrieve and compare quotes from multiple DEX protocols to ensure you get the best available rate for your token pair. {`

API: https://svc.blockdaemon.com/defi/v1/dex/quotes

`} ### Sample Request The **[DEX Swap Quotes API](https://docs.blockdaemon.com/reference/dexquotes)** fetches token swap quotes from multiple DEX protocols supported by Blockdaemon on a specified blockchain network. It enables users to compare swap rates across different DEXes for a specific token pair and input amount. ```curl curl --request GET \ --url 'https://svc.blockdaemon.com/defi/v1/dex/quotes?chainId=1&path=0xdac17f958d2ee523a2206206994597c13d831ec7,0x6B175474E89094C44Da98b954EedeAC495271d0F&amountIn=10000' \ --header 'X-API-Key: YOUR_API_KEY' \ --header 'Accept: application/json' ``` **Parameters**
Name Description
`chainId` The unique ID used to direct queries or transactions to the correct blockchain (e.g., `1` for Ethereum, `56` for BSC). Find a list of the supported chains [here](https://docs.blockdaemon.com/docs/defi-api-supported-protocols#supported-chains).
`path` Array of token addresses (e.g., `tokenIn,tokenOut`)
`amountIn` Amount of the input token, in wei (e.g., `1000000000000000000` for 1 ETH).
> đź‘Ť Adjusting Slippage > > You can adjust the slippage tolerance in subsequent steps during the execution of the swap by using the `slippage` or `amountOutMin` parameters. ### Sample Response The response contains an array of quotes sorted by `amountsOut` with the first entry represents the best quote (highest output amount for the given input). ```json { "status": 200, "msg": "success", "data": [ { "dexName": "0x", "dexId": "1600", "amountIn": "1000000", "path": [ "0xdac17f958d2ee523a2206206994597c13d831ec7", "0x6B175474E89094C44Da98b954EedeAC495271d0F" ], "amountsOut": [ "1000000", "1002502103426469968" ] }, { "dexName": "SushiswapV2", "dexId": "1100", "amountIn": "1000000", "path": [ "0xdac17f958d2ee523a2206206994597c13d831ec7", "0x6B175474E89094C44Da98b954EedeAC495271d0F" ], "amountsOut": [ "1000000", "1002189910250308204" ] }, { "dexName": "Kyberswap", "dexId": "2200", "amountIn": "1000000", "path": [ "0xdac17f958d2ee523a2206206994597c13d831ec7", "0x6B175474E89094C44Da98b954EedeAC495271d0F" ], "amountsOut": [ "1000000", "1002189910250308204" ] }, { "dexName": "CurveV2", "dexId": "1500", "amountIn": "1000000", "path": [ "0xdac17f958d2ee523a2206206994597c13d831ec7", "0x6B175474E89094C44Da98b954EedeAC495271d0F" ], "amountsOut": [ "1000000", "1000399509916717049" ] }, { "dexName": "BalancerV2", "dexId": "1400", "amountIn": "1000000", "path": [ "0xdac17f958d2ee523a2206206994597c13d831ec7", "0x6B175474E89094C44Da98b954EedeAC495271d0F" ], "amountsOut": [ "1000000", "1000363941967920384" ] }, { "dexName": "UniswapV3", "dexId": "1300", "amountIn": "1000000", "path": [ "0xdac17f958d2ee523a2206206994597c13d831ec7", "0x6B175474E89094C44Da98b954EedeAC495271d0F" ], "amountsOut": [ "1000000", "999896502154908225" ] }, { "dexName": "UniswapV2", "dexId": "1000", "amountIn": "1000000", "path": [ "0xdac17f958d2ee523a2206206994597c13d831ec7", "0x6B175474E89094C44Da98b954EedeAC495271d0F" ], "amountsOut": [ "1000000", "996499217880095575" ] } ] } ``` **Response Fields** | Field | Description | | ------------------ | ------------------------------------------------------------------------------------- | | `dexId`, `dexName` | Identifier and name of the DEX protocol (or `bridgeId` and `bridgeName` for bridges). | | `amountIn` | The amount of the input token to swap (in wei). | | `path` | An array of token addresses of the swap path (e.g., input and output tokens). | | `amountsOut` | An array with two elements: the input amount and the expected output amount. | *** ## Step 2: Check Allowance & Execute the Swap {`

API: https://svc.blockdaemon.com/defi/v1/dex/swap-with-approval

`} ### Sample Request The **[DEX Swap With Approval API](https://docs.blockdaemon.com/reference/dexswapwithapproval)** generates transaction payloads to perform a same chain swap on a supported DEX. It checks the current token allowance for the DEX router and adjusts the response accordingly. ```curl curl --request POST \ --url https://svc.blockdaemon.com/defi/v1/dex/swap-with-approval \ --header 'X-API-Key: YOUR_API_KEY' \ --header 'Content-Type: application/json' \ --data '{ "dexId": "1600", "path": [ "0xdac17f958d2ee523a2206206994597c13d831ec7", "0x6B175474E89094C44Da98b954EedeAC495271d0F" ], "amountIn": "1000000", "amountOutMin": "0", "to": "0xd8da6bf26964af9d7eed9e03e53415d37aa96045", "from": "0xd8da6bf26964af9d7eed9e03e53415d37aa96045" }' ``` **Parameters** | Field | Description | | -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `dexId` | The identifier of the DEX protocol. Find a list of the supported DEXs [here](https://docs.blockdaemon.com/docs/defi-api-supported-protocols#supported-dexs-protocols) . | | `path` | An array of token addresses of the swap path (e.g., input and output tokens). | | `amountIn` | The amount of the input token to swap (in wei). | | `amountOutMin` | The minimum acceptable output amount (set to `0` to accept any amount). | | `to` | The recipient address for the output tokens. | | `from` | The address initiating the swap. | > đź‘Ť Optimizing Amount > > Set `amountOutMin` based on the quote from [Step 1](https://docs.blockdaemon.com/docs/defi-api-execute-a-local-swap#step-1-check-the-swap-quote) to ensure a favorable swap rate. ### Sample Response The response includes an array of transactions: * If the allowance is **less than** `amountIn`, you'll get both an approval transaction and a swap transaction. * If the allowance is **sufficient**, only the swap transaction will be returned. ```json { "status": 200, "msg": "success", "data": [ { "chainId": "1", "from": "0xd8da6bf26964af9d7eed9e03e53415d37aa96045", "to": "0xdac17f958d2ee523a2206206994597c13d831ec7", "gas": "58723", "value": "0", "data": "0x095ea7b300000000000000000000000082d88875d64d60cbe9cbea47cb960ae0f04ebd4d00000000000000000000000000000000000000000000000000000000000f4240", "estimationCheck": true, "referenceId": "5969b1f73b124e819069f0e7bcdc4203" }, { "chainId": "1", "from": "0xd8da6bf26964af9d7eed9e03e53415d37aa96045", "to": "0x82d88875d64d60cbe9cbea47cb960ae0f04ebd4d", "gas": "500000", "value": "0", "data": "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", "estimationCheck": true, "referenceId": "5969b1f73b124e819069f0e7bcdc4203" } ] } ``` **Response Fields**
Field Description
`data` Array of transaction objects: * If **two transactions** are returned, the first is the approval transaction and the second is the swap transaction. * If **one transaction** is returned, it is the swap transaction.
`chainId` Chain ID for the transaction (source chain).
`from` Sender’s address.
`to` Contract address (token contract or bridge router).
`value` Amount of native token to send with the transaction (e.g., for gas fees, in wei).
`gas` Estimated gas limit for the transaction.
`data` Encoded transaction data (e.g., function call and arguments).
`referenceId` A unique identifier for tracking the request.
> 👍 Configuring Allowance Limits > > While the **[DEX Swap with Approval API](https://docs.blockdaemon.com/reference/dexswapwithapproval)** is convenient, some use-cases require customization of allowance limits. For this we offer individual **Allowance** and **[DEX Swap](https://docs.blockdaemon.com/reference/defi-dex-swap)** APIs *** ## Step 3: Sign the Transaction Once you’ve received the approval and swap transaction payloads, you need to sign each transaction before broadcasting it to the blockchain. **Signing** ensures that the transaction is authorized using the sender’s private key and is valid for execution. Follow the steps below: 1. **Retrieve** the approval and swap transaction objects from the response of the [DEX Swap with Approval API](https://docs.blockdaemon.com/reference/dexswapwithapproval). 2. **Sign** each transaction: 1. Use your preferred wallet (e.g., MetaMask, WalletConnect) or the Blockdaemon SDK 2. Make sure the `from` address in the transaction matches the wallet or SDK account initiating the swap. 3. The result will be a `rawTransaction` (e.g., a hexadecimal-encoded string). 3. **Verify** the signed transaction includes the correct nonce, gas, and to fields to prevent errors during broadcasting. *** ## Step 4: Broadcast the Signed Transaction Once you've signed the transaction(s), broadcast them to the blockchain to execute the same chain swap. {`

API: https://svc.blockdaemon.com/tx/v1/{blockchain_id}/send

`} ### Sample Request The **[Submit a Signed Transaction API](https://docs.blockdaemon.com/reference/txsend-txapi)** broadcasts a signed transaction to the specified blockchain network. This endpoint is used to submit both approval and swap transactions generated in [Step 3](https://docs.blockdaemon.com/docs/defi-api-execute-a-local-swap#step-3-sign-the-transaction). ```curl curl --request POST \ --url https://svc.blockdaemon.com/tx/v1/ethereum-mainnet/send \ --header 'X-API-Key: YOUR_API_KEY' \ --header 'Content-Type: application/json' \ --data '{ "tx": "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" }' ``` **Parameters** | Parameter | Description | | --------------- | ----------------------------------------------------------------------------------------------- | | `blockchain_id` | Either a hyphen-separated protocol-network pair like `ethereum-mainnet` or the `chain-network`. | | `tx` | The signed transaction. | ### Sample Response The response includes the **transaction hash**, which you can use to track its status via the [Get a Transaction API](https://docs.blockdaemon.com/docs/defi-api-execute-a-local-swap#step-5-verify-the-transaction). ```json { "id": "9c8ac345b443dd10a418ea0beaa320ef233dbae5590be2a11ac090e0e9839c1c" } ``` *** ## Step 5: Verify the Transaction After executing the same chain swap, monitor the transaction to confirm its status and ensure the successful transfer of tokens. {`

API: https://svc.blockdaemon.com/universal/{version}/{protocol}/{network}/tx/{hash}

`} ### Sample Request The **[Get a Transaction API](https://docs.blockdaemon.com/reference/gettxbyhash)** verifies the status and details of a swap transaction after it's been signed and broadcast. ```curl curl --request GET \ --url https://svc.blockdaemon.com/universal/v1/bitcoin/mainnet/tx/71d4f3412ec11128bbd9ce988d5bff2ec3bb6ea3953c8faf189d88ae49de9f7a \ --header 'X-API-Key: YOUR_API_KEY' \ --header 'Content-Type: application/json' ``` **Parameters** | Field | Description | | ---------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `protocol` | The protocol used for the transaction. | | `network` | The blockchain network where the transaction was executed (e.g., `ethereum-mainnet`, `polygon-mainnet`). | | `hash` | The unique transaction hash generated after signing and broadcasting the swap transaction. You can use this to track the transaction on a block explorer. See [Step 4](https://docs.blockdaemon.com/docs/defi-api-execute-a-local-swap#step-4-broadcast-the-signed-transaction). | ### Sample Response It returns detailed information about a specific transaction on a blockchain network. ```json { "id": "71d4f3412ec11128bbd9ce988d5bff2ec3bb6ea3953c8faf189d88ae49de9f7a", "block_id": "000000000000000000031911bca2ecf6c19ede467d81659f0c43a420ede1fd21", "date": 1667882555, "status": "completed", "num_events": 4, "meta": { "vsize": 144 }, "block_number": 762213, "confirmations": 140333, "events": [ { "id": "71d4f3412ec11128bbd9ce988d5bff2ec3bb6ea3953c8faf189d88ae49de9f7a-fee", "transaction_id": "71d4f3412ec11128bbd9ce988d5bff2ec3bb6ea3953c8faf189d88ae49de9f7a", "type": "fee", "denomination": "BTC", "date": 1667882555, "amount": 147, "decimals": 8 }, { "id": "input-55aeae5f9438ab72b52e51d0ebbe85d4509b6a853a60ebabe7bbd9dd33648c82-1", "transaction_id": "71d4f3412ec11128bbd9ce988d5bff2ec3bb6ea3953c8faf189d88ae49de9f7a", "type": "utxo_input", "denomination": "BTC", "source": "bc1qex0aqq8mxqfh4cpl62eg755836djjx20yzuuu8", "meta": { "addresses": [ "bc1qex0aqq8mxqfh4cpl62eg755836djjx20yzuuu8" ], "index": 1, "script": "0014c99fd000fb30137ae03fd2b28f52878e9b29194f", "script_type": "witness_v0_keyhash", "input_index": 0 }, "date": 1667882555, "amount": 81736, "decimals": 8 }, { "id": "71d4f3412ec11128bbd9ce988d5bff2ec3bb6ea3953c8faf189d88ae49de9f7a-0", "transaction_id": "71d4f3412ec11128bbd9ce988d5bff2ec3bb6ea3953c8faf189d88ae49de9f7a", "type": "utxo_output", "denomination": "BTC", "destination": "1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa", "meta": { "addresses": [ "1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa" ], "index": 0, "script": "76a91462e907b15cbf27d5425399ebf6f0fb50ebb88f1888ac", "script_type": "pubkeyhash" }, "date": 1667882555, "amount": 558, "decimals": 8 }, { "id": "71d4f3412ec11128bbd9ce988d5bff2ec3bb6ea3953c8faf189d88ae49de9f7a-1", "transaction_id": "71d4f3412ec11128bbd9ce988d5bff2ec3bb6ea3953c8faf189d88ae49de9f7a", "type": "utxo_output", "denomination": "BTC", "destination": "bc1qex0aqq8mxqfh4cpl62eg755836djjx20yzuuu8", "meta": { "addresses": [ "bc1qex0aqq8mxqfh4cpl62eg755836djjx20yzuuu8" ], "index": 1, "script": "0014c99fd000fb30137ae03fd2b28f52878e9b29194f", "script_type": "witness_v0_keyhash" }, "date": 1667882555, "amount": 81031, "decimals": 8 } ] } ``` **Response Fields** | Field | Description | | --------------- | ------------------------------------------------------------------------------------- | | `id` | Unique transaction ID (same as `hash`). | | `block_id` | Identifier of the block where this transaction was included. | | `block_number` | Block height where the transaction was confirmed. | | `date` | Unix timestamp of when the transaction occurred. | | `status` | Status of the transaction (e.g., `"completed"`). | | `confirmations` | Number of confirmations since the transaction was included in a block. | | `num_events` | Total number of events (e.g., inputs, outputs, fees) associated with the transaction. | | `meta.vsize` | Virtual size of the transaction in vbytes (used for fee calculation in Bitcoin). | | `events[]` | Array of transaction-related events such as UTXO inputs, outputs, and fee. | ## đź‘‹ Need Help? Contact us through [email](mailto:support@blockdaemon.com) or our [support page](https://www.blockdaemon.com/support) for any issues, bugs, or assistance you may need.