About the merge PDF tool
The merge PDF tool combines two or more PDF documents into a single file. It is intended for everyday tasks such as combining invoices, joining scanned pages, or assembling several shorter documents into one longer file for sharing or archiving.
All processing happens in your browser using JavaScript. When you select files and click merge, the files are read directly from your device, and the combined result is generated and downloaded from the same browser session. Your files are not uploaded to any server.
This approach has practical advantages. There is no waiting time for uploads, no server side copies of your documents, and the tool remains usable even on a slow connection once the page has loaded.
How to merge PDF files
Using the tool takes only a few steps.
- Select two or more PDF files from your device.
- Review the list to confirm the files and their order.
- Remove any file you do not want to include.
- Click the merge button to combine the files.
- Download the combined PDF from your browser.
The files are combined in the order they appear in the list. Each file's pages are added in their original order, so the first file's first page becomes the first page of the combined document, and so on.
How merging works
A PDF file is made up of pages, and each page is stored as a collection of objects. When two or more PDF files are merged, the tool reads the page structure of each file in turn and adds those pages to a new document, preserving the content of each original page.
Text, images, vector graphics, and most embedded elements are preserved during this process. The merge does not re render pages, which means the visual content of each original page remains the same.
Some elements, such as interactive form fields, JavaScript, or certain annotations, may not be preserved in every case, particularly if they refer to resources that are defined at the document level rather than the page level.
Practical uses
- Combining several scanned documents into one file.
- Joining monthly statements, invoices or receipts into a single archive.
- Assembling separate chapters of a report into one document.
- Merging application forms, attachments and supporting documents.
- Grouping related PDFs before emailing or uploading them.
The tool is designed for common, everyday merging tasks. Very large or unusual PDFs may be slower to process and, in rare cases, may not merge cleanly if they contain non standard features.
Limitations
- Encrypted or password protected PDFs may not merge.
- The order of the original files must be set manually in the file list.
- Page level rotation or cropping is not applied during merging.
- Form fields, bookmarks and some interactive features may not transfer.
- Very large files may be slow to process on devices with limited memory.
If a document contains protected content or unusual features, open it in a trusted PDF reader and inspect the result after merging.
Frequently asked questions
Important information
This tool is provided for general informational and personal use. It performs PDF merging in your browser and does not provide legal, financial or professional advice.
Always keep an original copy of any important file before processing it. Although merging is designed to preserve content faithfully, PDF processing always involves rewriting the file structure, and rare cases of incompatibility can occur with unusual or non standard documents.