> ## Documentation Index
> Fetch the complete documentation index at: https://docs.validationcloud.io/llms.txt
> Use this file to discover all available pages before exploring further.

# gettxoutproof

Returns a hex-encoded proof that “txid” was included in a block.

NOTE: By default this function only works sometimes. This is when there is an unspent output in the utxo for this transaction. To make it always work, you need to maintain a transaction index, using the -txindex command line option or specify the block in which the transaction is included manually (by blockhash).

This method will use `10` [Compute Units](/nodeapi/about/billing).

***

## **Reference:** [**Here**](https://developer.bitcoin.org/reference/rpc/gettxoutproof.html)

## **Parameters**

**`txids`** - json array, required

The txids to filter

```json theme={"theme":{"light":"github-light","dark":"github-dark-default"}}
[
  "txid",    (string) A transaction hash
  ...
]
```

**`blockhash`** - string, optional

If specified, looks for txid in the block with this hash

## Returns

| Name | Type | Description |
| - | - | - |
| str | string | A string that is a serialized, hex-encoded data for the proof. |


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