# GET /v4/internal/transactions/find-creation-hash

_Merkl API_

> Find Creation Transaction Hash

This endpoint searches for the transaction hash that created a campaign by chain ID and campaign ID. Uses binary search with archive node calls to efficiently locate the creation block, then searches for NewCampaign events. Returns the transaction hash, block number, and explorer URL if found, or null values if not found.

### Query parameters

- `chainId` (string | number) _(required)_
- `campaignId` (string) _(required)_

### Header parameters

- `chainId` (string | number) _(required)_
- `campaignId` (string) _(required)_

## Responses

- **200** Response for status 200

## Example request

```bash
curl -X GET "https://api.merkl.xyz//v4/internal/transactions/find-creation-hash?chainId=<chainId>&campaignId=<campaignId>" \
  -H "x-api-key: YOUR_API_KEY" \
  -H "chainId: <chainId>" \
  -H "campaignId: <campaignId>"
```