PDF File Merger using ConvertAPI - n8n Workflow

Users needing to automatically consolidate large batches of PDF documents.
Developers seeking advanced n8n templates for integrating external file conversion APIs.
Anyone requiring a reliable n8n workflow for document processing and management.
Organizations looking to automate file operations via a core n8n node setup.

This powerful n8n workflow demonstrates how to streamline PDF document management by automating the often tedious process of merging multiple files. Instead of manually combining documents, this n8n automation handles the entire process programmatically.

The workflow utilizes multiple n8n HTTP Request nodes to first fetch the source PDFs and then interface with the ConvertAPI service for the actual merging. This robust setup makes it an excellent example for those looking to customize n8n templates for specialized document operations. After the merging is complete, this efficient n8n workflow leverages the Read/Write File n8n node to securely save the final, combined file to your local or connected file system. This ready-to-use n8n template significantly simplifies complex documentation handling.

The process begins with the manual n8n trigger, allowing you to easily test the entire n8n workflow.

1. File Downloads: Two sequential HTTP Request n8n nodes are executed to download the individual PDF files from their remote URLs. Crucially, the response from these requests is set to 'File' format, storing the binary data in separate properties (data1 and data2).


2. API Call: The core PDF merge API HTTP Request n8n node takes both binary data streams (data1 and data2). This n8n node is configured to use multipart form data and authenticates using generic HTTP Query Authentication (for your ConvertAPI secret). It submits the files to the ConvertAPI merging endpoint.


3. Output Handling: ConvertAPI returns the single merged PDF file, which is stored in the workflow's binary data stream as data.


4. Save Result: Finally, the Read/Write File n8n node (Write Result File to Disk) takes the resulting merged binary data (=data) and writes it to disk, naming the output file document.pdf. This completes the automated n8n workflow.

1. Import: Copy the provided n8n workflow JSON and import it directly into your n8n instance.


2. ConvertAPI Setup: This n8n workflow requires a ConvertAPI account. Sign up and obtain your secret key.


3. Credentials: Locate the PDF merge API HTTP Request n8n node. You will need to create or update the httpQueryAuth credential. Configure the credential to use your ConvertAPI secret key as a query parameter (typically named Secret or specified by ConvertAPI documentation).


4. Testing: Click the 'When clicking ‘Test workflow’' n8n trigger to run the automation and verify that document.pdf is created in your n8n temporary file directory or designated path.


5. Customization: Adjust the URLs in the initial HTTP Request n8n nodes to download your specific source documents.

When clicking ‘Test workflow’ (Manual Trigger)
Function: Acts as the initial n8n trigger to manually start the n8n workflow.
Key Configuration: None (Standard manual execution).
Download first remote PDF File / Download second PDF File (HTTP Request n8n node)
Function: Fetches binary file data from specified remote URLs.
Key Configuration: Response format is set to File and the output properties are defined as data1 and data2 respectively, crucial for passing binary data through the n8n workflow.
PDF merge API HTTP Request (HTTP Request n8n node)
Function: Sends the two downloaded binary files to the ConvertAPI merging service using a POST request.
Key Configuration: Uses multipart-form-data content type; Body Parameters map data1 and data2 to files[0] and files[1]; Authentication uses a generic HTTP Query Auth credential; The response file is mapped to the output property data.
Write Result File to Disk (Read/Write File n8n node)
Function: Saves the final merged PDF document to the file system.
Key Configuration: Operation is Write; File Name is document.pdf; Data Property Name uses the expression =data to retrieve the merged binary file output from the previous n8n node.