Transaction Formats by txType

Reference examples of the transaction payload SwapKit returns for each txType.

Every /v3/quote and /v3/swap route that includes a transaction returns two related fields:

• tx — the transaction payload to sign and broadcast.

• txType — a tag identifying the payload's format, so you know how to decode and sign it.

The shape of tx depends on txType. Some chains return a JSON object (EVM, Cosmos, Tron); others return an already-serialized string (Bitcoin PSBT, Solana, Ripple, NEAR, Sui, Cardano, Zcash). This page catalogs the exact format for each txType with a real example response.

For how these payloads are signed and how to verify the signature, see Transaction Payload Signing. Object tx types are canonicalized with RFC 8785 (JCS) before hashing; string tx types are hashed verbatim.

How to reproduce an example

To fill in a section below, run one real swap on that chain and paste the response:

1. Call /v3/quote with a sellAsset on the target chain and a funded sourceAddress, then pick a route.

2. Request the transaction using that route's nextActions entry — it gives you the method, url, and payload to send, so you don't build the /swap call yourself.

3. From the response, copy the route's txType, tx, and — if signing is enabled — meta.signedTx / meta.signature / meta.signedTxString into the matching section.

See the /v3/quote and /v3/swap docs for the full request/response contract.

---

Object tx types

These return tx as a JSON object. The signed pre-image is the RFC 8785 (JCS) canonical JSON of the object — see Transaction Payload Signing.

EVM

• txType: EVM

• tx shape: object ({ from, to, data, value, gas, gasPrice, ... })

• Chains: Ethereum, BSC, Avalanche, Arbitrum, Base, Polygon

• Example sell asset: ETH.ETH

Example response (tx + meta)

{
  "txType": "EVM",
  "tx": {
    "to": "0xRECIPIENT_ADDRESS",
    "from": "0xYOUR_SOURCE_ADDRESS",
    "gas": "0x6270",
    "gasPrice": "0x7ecbe4e",
    "value": "0x2386f26fc10000",
    "data": "0x"
  },
  "meta": {
    "txType": "EVM",
    "signedTxString": "{\"data\":\"0x\",\"from\":\"0xYOUR_SOURCE_ADDRESS\",\"gas\":\"0x6270\",\"gasPrice\":\"0x7ecbe4e\",\"to\":\"0xRECIPIENT_ADDRESS\",\"value\":\"0x2386f26fc10000\"}",
    "signedTx": "<base64url(SHA-256 hex of signedTxString)>",
    "signature": "<base64url ES256 signature>"
  }
}

Notes: meta.signedTxString has the keys in alphabetical order (data, from, gas, gasPrice, to, value) — not the order they appear in tx. That's the RFC 8785 canonical form.

COSMOS

• txType: COSMOS

• tx shape: object (Cosmos SDK transaction)

• Chains: Cosmos Hub (GAIA), and other Cosmos SDK chains

• Example sell asset: GAIA.ATOM

Example response (tx + meta)

{
  "txType": "COSMOS",
  "tx": {
    "memo": "=:e:0xYOUR_DEST:659671/1/0:-_/nc:15/0",
    "accountNumber": 3695266,
    "sequence": 0,
    "chainId": "cosmoshub-4",
    "msgs": [
      {
        "typeUrl": "/cosmos.bank.v1beta1.MsgSend",
        "value": {
          "amount": [{ "amount": "10000000", "denom": "uatom" }],
          "fromAddress": "cosmos1YOUR_SOURCE",
          "toAddress": "cosmos1VAULT"
        }
      }
    ],
    "fee": { "amount": [{ "denom": "uatom", "amount": "5000" }], "gas": "200000" }
  },
  "meta": {
    "txType": "COSMOS",
    "signedTxString": "{\"accountNumber\":3695266,\"chainId\":\"cosmoshub-4\",\"fee\":{\"amount\":[{\"amount\":\"5000\",\"denom\":\"uatom\"}],\"gas\":\"200000\"},\"memo\":\"=:e:0xYOUR_DEST:659671/1/0:-_/nc:15/0\",\"msgs\":[{\"typeUrl\":\"/cosmos.bank.v1beta1.MsgSend\",\"value\":{\"amount\":[{\"amount\":\"10000000\",\"denom\":\"uatom\"}],\"fromAddress\":\"cosmos1YOUR_SOURCE\",\"toAddress\":\"cosmos1VAULT\"}}],\"sequence\":0}",
    "signedTx": "<base64url digest>",
    "signature": "<base64url ES256 signature>"
  }
}

Notes: tx is a JSON object, canonicalized with RFC 8785 (JCS) before hashing — keys sorted recursively (nested objects too). Reproduce with a JCS canonicalizer, or just hash meta.signedTxString

TRON

• txType: TRON

• tx shape: object (Tron transaction; may be an EVM-style object for TRC-20/contract calls)

• Chains: Tron

• Example sell asset: TRON.TRX

Example response (tx + meta)

{
  "txType": "TRON",
  "tx": {
    "visible": true,
    "txID": "0f29b0bced8061478386652a4b07c0c8654561a502daf67ad83039db32c7d1f1",
    "raw_data": {
      "contract": [
        {
          "parameter": {
            "value": {
              "owner_address": "TYOUR_SOURCE_ADDRESS",
              "to_address": "TVAULT_ADDRESS",
              "amount": 55000000
            },
            "type_url": "type.googleapis.com/protocol.TransferContract"
          },
          "type": "TransferContract"
        }
      ],
      "ref_block_bytes": "f952",
      "ref_block_hash": "4b675bed33dccae0",
      "expiration": 1785273270000,
      "timestamp": 1785272972258,
      "data": "3d3a653a…2f30"
    },
    "raw_data_hex": "0a02f95222084b675bed33dccae0…e2e7bed4fa33"
  },
  "meta": {
    "txType": "TRON",
    "signedTxString": "{\"raw_data\":{\"contract\":[{\"parameter\":{\"type_url\":\"type.googleapis.com/protocol.TransferContract\",\"value\":{\"amount\":55000000,\"owner_address\":\"TYOUR_SOURCE_ADDRESS\",\"to_address\":\"TVAULT_ADDRESS\"}},\"type\":\"TransferContract\"}],\"data\":\"3d3a653a…2f30\",\"expiration\":1785273270000,\"ref_block_bytes\":\"f952\",\"ref_block_hash\":\"4b675bed33dccae0\",\"timestamp\":1785272972258},\"raw_data_hex\":\"0a02f952…bed4fa33\",\"txID\":\"0f29…d1f1\",\"visible\":true}",
    "signedTx": "<base64url digest>",
    "signature": "<base64url ES256 signature>"
  }
}

Notes: tx is a JSON object (native Tron format: visible, txID, raw_data, raw_data_hex), canonicalized with RFC 8785 (JCS) — keys sorted recursively (top-level → raw_data, raw_data_hex, txID, visible; inside raw_data → contract, data, expiration, ref_block_bytes, ref_block_hash, timestamp; etc.).

---

String tx types

These return tx as an already-serialized string. The string is the exact signable bytes and is hashed verbatim (no canonicalization) — see Transaction Payload Signing.

PSBT

• txType: PSBT

• tx shape: string (base64-encoded PSBT)

• Chains: Bitcoin, Litecoin, Dogecoin, Bitcoin Cash, Dash

• Example sell asset: BTC.BTC

Example response (tx + meta)

{
  "txType": "PSBT",
  "tx": "cHNidP8BAKQCAAAAAyFxJZDlxNYA3/36dLs5h2/…BcYepUBX5AAA",
  "meta": {
    "txType": "PSBT",
    "signedTxString": "cHNidP8BAKQCAAAAAyFxJZDlxNYA3/36dLs5h2/…BcYepUBX5AAA",
    "signedTx": "<base64url(SHA-256 hex of signedTxString)>",
    "signature": "<base64url ES256 signature>"
  }
}

Notes: For a PSBT (string) tx, meta.signedTxString is identical to tx — string txs are hashed verbatim, not canonicalized.

SOLANA

• txType: SERIALIZED_BASE64

• tx shape: string (base64-serialized Solana transaction)

• Chains: Solana

• Example sell asset: SOL.SOL

Example response (tx + meta)

{
  "txType": "SERIALIZED_BASE64",
  "tx": "AQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA…AwEGBAICAA==",
  "meta": {
    "txType": "SERIALIZED_BASE64",
    "signedTxString": "AQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA…AwEGBAICAA==",
    "signedTx": "<base64url(SHA-256 hex of signedTxString)>",
    "signature": "<base64url ES256 signature>"
  }
}

Notes: tx is a base64-serialized Solana transaction — a string, hashed verbatim (signedTxString === tx)

RIPPLE

• txType: RIPPLE

• tx shape: string

• Chains: XRP Ledger

• Example sell asset: XRP.XRP

Example response (tx + meta)

{
  "txType": "RIPPLE",
  "tx": "{\"Account\":\"rYOUR_XRP_ADDRESS\",\"Amount\":\"10000000\",\"Destination\":\"rVAULT_ADDRESS\",\"TransactionType\":\"Payment\",\"Memos\":[{\"Memo\":{\"MemoData\":\"<hex-encoded THORChain memo>\"}}],\"Flags\":0,\"Sequence\":105916205,\"Fee\":\"12\",\"LastLedgerSequence\":105916293}",
  "meta": {
    "txType": "RIPPLE",
    "signedTxString": "<identical to tx>",
    "signedTx": "<base64url digest>",
    "signature": "<base64url ES256 signature>"
  }
}

Notes: tx is a JSON string (an XRPL Payment serialized with JSON.stringify). Even though it contains JSON, RIPPLE is a string txType — hashed verbatim. Do not JSON.parse + re-stringify it and do not canonicalize it: the keys are in XRPL order (Account, Amount, Destination,...), and any re-serialization changes the bytes and breaks verification. Hash the raw string exactly as received (meta.signedTxString, which equals tx).

NEAR

• txType: NEAR

• tx shape: string

• Chains: NEAR

• Example sell asset: NEAR.NEAR

Example response (tx + meta)

{
  "txType": "NEAR",
  "tx": "QAAAAGY5ZDEwZjY3YzE1YTU5YTI2MDIzNzNkYjZlMmRmZDEx…QLzQGAAAAAAA=",
  "meta": {
    "txType": "NEAR",
    "signedTxString": "QAAAAGY5ZDEwZjY3YzE1YTU5YTI2MDIzNzNkYjZlMmRmZDEx…QLzQGAAAAAAA=",
    "signedTx": "<base64url(SHA-256 hex of signedTxString)>",
    "signature": "<base64url ES256 signature>"
  }
}

Notes: tx is a serialized NEAR transaction (a string, hashed verbatim: signedTxString === tx). String type → no canonicalization; binding check is sha256(signedTxString).

SUI

• txType: SUI

• tx shape: string

• Chains: Sui

• Example sell asset: SUI.SUI

Example response (tx + meta)

{
  "txType": "SUI",
  "tx": "AAACAAgAuh3SBQAAAAAgKbUATN1/dlfYgu135boj9uTDvIhgZ/V1lsp0J7yK5J4CAg…gPD6AgAAAAAA",
  "meta": {
    "txType": "SUI",
    "signedTxString": "AAACAAgAuh3SBQAAAAAgKbUATN1/dlfYgu135boj9uTDvIhgZ/V1lsp0J7yK5J4CAg…gPD6AgAAAAAA",
    "signedTx": "<base64url digest>",
    "signature": "<base64url ES256 signature>"
  }
}

Notes: tx is base64 Sui transaction bytes (txBytes.toBase64()) — a string, hashed verbatim (signedTxString === tx). No canonicalization.

CARDANO

• txType: CBOR

• tx shape: string (CBOR-encoded transaction)

• Chains: Cardano

• Example sell asset: ADA.ADA

Example response (tx + meta)

{
  "txType": "CBOR",
  "tx": "84a40081825820bdfd6582d231bc8f4db1a2973d98159dda73e719461bff1a0edc7ef64bf3d62d00…031a0b8bccd1a0f5f6",
  "meta": {
    "txType": "CBOR",
    "signedTxString": "84a40081825820bdfd6582d231bc8f4db1a2973d98159dda73e719461bff1a0edc7ef64bf3d62d00…031a0b8bccd1a0f5f6",
    "signedTx": "<base64url digest>",
    "signature": "<base64url ES256 signature>"
  }
}

Notes: tx is an unsigned Cardano transaction as a CBOR hex string — hashed verbatim (signedTxString === tx). No canonicalization.

STELLAR

• txType: STELLAR

• tx shape: string (base64 XDR)

• Chains: Stellar

• Example sell asset: XLM.XLM

Example response (tx + meta)

{
  "txType": "STELLAR",
  "tx": "AAAAAgAAAABJsaHU9Ev9qTHMGCvskZX0JUWmI+brCIUIPhCqEsbi5w…AAAAAAA==",
  "meta": {
    "txType": "STELLAR",
    "signedTxString": "AAAAAgAAAABJsaHU9Ev9qTHMGCvskZX0JUWmI+brCIUIPhCqEsbi5w…AAAAAAA==",
    "signedTx": "<base64url(SHA-256 hex of signedTxString)>",
    "signature": "<base64url ES256 signature>"
  }
}

Notes: tx is a base64 XDR-encoded Stellar transaction envelope (a string, hashed verbatim: signedTxString === tx). String type → no canonicalization; binding check is sha256(signedTxString).

Zcash (unsigned)

• txType: zcash-unsigned

• tx shape: string

• Chains: Zcash

• Example sell asset: ZEC.ZEC

Example response (tx + meta)

{
  "txType": "zcash-unsigned",
  "tx": "UENaVAEAAAAFis6ctQLbrJS9AwEA8t7RAY…AAAA==",
  "meta": {
    "txType": "zcash-unsigned",
    "signedTxString": "UENaVAEAAAAFis6ctQLbrJS9AwEA8t7RAY…AAAA==",
    "signedTx": "<base64url(SHA-256 hex of signedTxString)>",
    "signature": "<base64url ES256 signature>"
  }
}

Notes: tx is a base64 PCZT (Partially Created Zcash Transaction — the shielded path; transparent ZEC returns PSBT). A string, hashed verbatim.