Merge Multiple PDF Files with CustomJS API

This n8n template demonstrates how to download multiple PDF files from public URLs and merge them into a single PDF using the PDF Toolkit from www.customjs.space.

@custom-js/n8n-nodes-pdf-toolkit

Notice

Community nodes can only be installed on self-hosted instances of n8n.

What this workflow does

Downloads** each PDF using an HTTP Request. Populates* files into an array with Merge* node from n8n. Merges** all downloaded PDFs using the Merge PDF node from the @custom-js/n8n-nodes-pdf-toolkit. Writes** the final merged PDF to disk.

Requirements

Self-hosted** n8n instance CustomJS API key** for merging multiple PDF files. PDF files to be merged** to be converted into a PDF

Workflow Steps:

Manual Trigger:

Runs with user interaction.

HTTP Request Node For PDF Download:

Pass urls for PDF files to merge.

Merge Node For Array Population:

Just populates two files into an array.

Merge PDF files: Uses the CustomJS node to merge the incoming PDF files into a single PDF file. If size of PDF files exceeds 6MB, you can simply pass an array of URLs for PDF files.

Usage

Get API key from customJS

Sign up to customJS platform. Navigate to your profile page Press "Show" button to get API key Set Credentials for CustomJS API on n8n

Copy and paste your API key generated from CustomJS here.

Design workflow

A Manual Trigger for starting workflow. Two HTTP Request Nodes for downloading PDF files. A Merge Node for populating files as an array. Merge PDFs node for merging files Write to Disk node for saving merged PDF file.

You can replace logic for triggering and returning results. For example, you can trigger this workflow by calling a webhook and get a result as a response from webhook. Simply replace Manual Trigger and Write to Disk nodes.

Perfect for

Bundling reports or invoices. Generating document sets from external sources. Automating PDF handling without writing custom code