> For the complete documentation index, see [llms.txt](https://zpass.docs.aleo.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://zpass.docs.aleo.org/zpass-sdk/overview/verifyonchain.md).

# verifyOnChain

## Description

The `verifyOnChain` static method verifies an on-chain ZPass proof by checking the transaction on the blockchain.

### Parameters

* **`options` (VerifyOnChainOptions)**: An object containing:
  * **`transactionId` (string)**: The ID of the transaction to verify
  * **`url` (string, optional)**: Custom API endpoint URL (defaults to "<https://api.explorer.provable.com/v1>")

### Returns

Returns a Promise that resolves to an object containing:

* **`hasExecution` (boolean)**: Whether the transaction contains an execution, only true if the transaction has a valid execution finalized on-chain (meaning the transaction proof is valid).
* **`outputs` (Output\[])**: Array of transaction outputs

### Example

```javascript
const result = await ZPass.verifyOnChain({
    transactionId: "at1xyz...",
    url: "http://localhost:3030"
});
```