Swap

POST https://swap-api.sodae.io/v1/swap
Content-Type: application/json

The swap runs the same route selection as /v1/quote, then compiles the route into one transaction for the wallet you name. The server never holds keys. You sign and send.

Request

{
  "input_mint": "SOL",
  "output_mint": "USDC",
  "amount_in_atoms": 1000000000,
  "user_wallet": "7Zq…",
  "slippage_bps": 50,
  "max_hops": 3,
  "max_price_impact_bps": 1000,
  "priority_fee_lamports": 100000
}

Field	Type	Default	Description
`input_mint`	string	required	Mint or symbol of the token you sell
`output_mint`	string	required	Mint or symbol of the token you buy
`amount_in_atoms`	integer	required	Input amount in base units
`user_wallet`	string	required	Public key that will sign and pay fees
`slippage_bps`	integer	`50`	Slippage tolerance
`max_hops`	integer	`3`	Longest path considered
`max_price_impact_bps`	integer	`1000`	Same ceiling as `/v1/quote`
`min_liquidity`	number	server default	Same floor as `/v1/quote`
`max_routes`	integer	`4096`	Same cap as `/v1/quote`
`priority_fee_lamports`	integer	`0`	Priority fee added to the transaction, in lamports
`input_token_program`	string	from the mint	Override the input token program
`output_token_program`	string	from the mint	Override the output token program

The token program is resolved from the mint. Only set an override when you already know the owning program; a wrong value fails on chain.

Response

{
  "tx_base64": "gQEAAQ…",
  "recent_blockhash": "9bKxN…",
  "last_valid_block_height": 351234567,
  "lookup_tables": [],
  "provider": "soda",
  "route": {
    "input_mint": "So111…",
    "output_mint": "EPjF…",
    "in_atoms": 1000000000,
    "out_atoms": 104555250,
    "out_ui": 104.55525,
    "min_out_atoms": 104032473,
    "slippage_bps": 50,
    "price_impact_bps": 0,
    "legs": [ … ],
    "alternative_routes": [],
    "splits": []
  }
}

Field	Description
`tx_base64`	The unsigned transaction, base64
`recent_blockhash`	Blockhash the transaction was built with
`last_valid_block_height`	Last block height at which it can land. Use both to confirm
`lookup_tables`	Always empty. Transaction v1 has no lookup tables
`route`	The quote this transaction executes. `legs` is the single route; `splits` is populated when a split is served

route.out_atoms is the quoted output. route.min_out_atoms is enforced on chain. Output SOL arrives as wrapped SOL.

Transaction format

The transaction is Solana transaction format v1. It starts with the version byte 0x81, not a signature count.

@solana/web3.js 1.x and other decoders that expect legacy or v0 messages throw on it. Decode and sign with a library that understands transaction v1, such as @solana/kit 3 or later, and send the serialized bytes with any RPC’s sendTransaction. Wallets that implement the Solana Wallet Standard sign v1 transactions through their normal sign method.

Sign and send

Decode

Base64-decode tx_base64 into a v1 transaction.

Sign

Sign with the key for user_wallet. The transaction has no other signers.

Send

Submit the signed bytes to your RPC. Skipping preflight is safe only if you simulated yourself.

Confirm

Poll the signature until it is confirmed, or until the chain passes last_valid_block_height, at which point the transaction can no longer land and you should request a new swap.

Swap transactions are not simulated server side. To fail before paying a fee, simulate the signed transaction against your RPC first.

Errors

Status	Body	Meaning
400	`{"error":"invalid input_mint"}`, `{"error":"invalid output_mint"}`, `{"error":"invalid user_wallet"}`	A mint or the wallet did not parse
404	`{"error":"no_route"}`	No route, as for `/v1/quote`
422	`{"error":"price_impact_too_high","code":"…"}`	Impact ceiling, as for `/v1/quote`
422	`{"error":"round_trip_unsound","code":"…"}`	Round-trip guard, as for `/v1/quote`
500	`{"error":"…","pool":"…"}`	The route could not be compiled. `pool` names the leg that failed when known
503	`{"error":"compute pool unavailable"}`	Capacity exhausted. Retry with backoff

A branch that cannot be built is excluded and selection re-runs before a 500 is returned, so a 500 means no buildable route remained.

Get started

API

Guides

Reference

Request

Response

Transaction format

Sign and send

Errors

​Request

​Response

​Transaction format

​Sign and send

​Errors

Request

Response

Transaction format

Sign and send

Errors