Transparent tracking pixel for email open detection

📌 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