Say you have the serialized, hex-encoded string representing a transaction and want to return the transaction data in a JSON object.

decoderawtransaction is an RPC function that returns a JSON object representing the serialized, hex-encoded transaction.

The decoderawtransaction takes two arguments:

1. hexstring: This is the transaction hex-encoded string. This argument is required.

2. iswitness: The optional second argument takes a boolean value (true or false), whether the transaction hex is a serialized witness transaction.

If iswitness is absent, heuristic tests will be used to decode the raw transaction. If true, only witness deserialization will be tried. If false, only non-witness deserialization will be tried.

For example, the hex-encoded string of the coinbase transaction of block 84,000 is:

01000000010000000000000000000000000000000000000000000000000000000000000000ffffffff0804a3b2311b028611ffffffff0100f2052a010000004341040ea70cd9bc1996e8b777b2f17d9b680671c4b0b2474991b8b029d574e7a12c44e8e4a06fa4cb14983b89f19577259eb5022ca655d8120fa3ac7a03d7e5da4176ac00000000

Grabing the transaction hex string, you can use the decoderawtransaction command as below:

bitcoin-cli decoderawtransaction 01000000010000000000000000000000000000000000000000000000000000000000000000ffffffff0804a3b2311b028611ffffffff0100f2052a010000004341040ea70cd9bc1996e8b777b2f17d9b680671c4b0b2474991b8b029d574e7a12c44e8e4a06fa4cb14983b89f19577259eb5022ca655d8120fa3ac7a03d7e5da4176ac00000000

Output:

{
  "hash": "9faa752b6099a8fa58681580540a8450b02304535d97cdd5bcd0617526dd374f",
  "locktime": 0,
  "size": 135,
  "txid": "9faa752b6099a8fa58681580540a8450b02304535d97cdd5bcd0617526dd374f",
  "version": 1,
  "vin": [
    {
      "coinbase": "04a3b2311b028611",
      "sequence": 4294967295
    }
  ],
  "vout": [
    {
      "n": 0,
      "scriptPubKey": {
        "asm": "040ea70cd9bc1996e8b777b2f17d9b680671c4b0b2474991b8b029d574e7a12c44e8e4a06fa4cb14983b89f19577259eb5022ca655d8120fa3ac7a03d7e5da4176 OP_CHECKSIG",
        "desc": "pk(040ea70cd9bc1996e8b777b2f17d9b680671c4b0b2474991b8b029d574e7a12c44e8e4a06fa4cb14983b89f19577259eb5022ca655d8120fa3ac7a03d7e5da4176)#rzwvwd7r",
        "hex": "41040ea70cd9bc1996e8b777b2f17d9b680671c4b0b2474991b8b029d574e7a12c44e8e4a06fa4cb14983b89f19577259eb5022ca655d8120fa3ac7a03d7e5da4176ac",
        "type": "pubkey"
      },
      "value": 50.0
    }
  ],
  "vsize": 135,
  "weight": 540
}

The decoderawtransaction RPC command provides a way to decode and interpret the raw, hex-encoded transaction data returned by getrawtransaction.

While getrawtransaction retrieves the raw transaction data in hexadecimal format, decoderawtransaction parses and formats this data into a more human-readable and structured JSON object.

Of course, by specifying verbosity=true, you can use the getrawtransactionto get a more human-readable and structured JSON object of a Bitcoin transaction.

However, some Bitcoin scripts, especially complex ones, are represented in raw hexadecimal form in the raw transaction data. decoderawtransaction interprets and decodes these scripts, providing a more user-friendly representation of the script operations and conditions.

Also, the decoderawtransaction provides details about the script signatures and public keys involved in the transaction, which can be valuable when examining the transaction’s security and verification aspects.