## Description This workflow serves a **1x1 transparent PNG image** via a webhook, which can be embedded in an email to **track when the email is opened**. When the image is loaded by the recipient's email client, the webhook is triggered, optionally capturing a `userId` to identify who opened the email. ## Workflow Steps 1. **Webhook Trigger** (`Request img`) - **Path:** `/webhook/change-with-your-id` - Triggered by an HTTP request (e.g., when the image is loaded in an email). - Accepts a query parameter `id` to identify the recipient. 2. **Set Base64 Data** (`Create data pix`) - Creates a variable `data` containing a Base64-encoded transparent PNG image (1x1 pixel). 3. **Convert to Binary** (`Create img bin`) - Converts the Base64 `data` string into a binary file. - Sets MIME type to `image/png`. 4. **Respond to Webhook** (`Respond to Webhook`) - Sends the binary image file in the HTTP response. 5. **Logging** (`Do anything to log`) - Placeholder node to log or process the `id` or request metadata. - You can access the `id` using `{{$json[query][id]}}`. - You can also use any parameter you want ## How to Use in Emails Embed the image in an HTML email like this: ```html <img src=https://<your-n8n-instance>/webhook/db4880e7-2134-4994-94e5-a4a3aa120440?id=1234 width=1 height=1 alt /> ``` When the email is opened and the image is loaded, the workflow will be triggered. ## Notes - Some email clients block images by default; this may prevent tracking. - You can enhance the workflow to store open events in a database, log the timestamp, IP, or user agent. - Make sure to comply with data privacy and consent regulations (e.g., GDPR).