How to merge PDF files

  1. 1

    Upload your PDFs

    Click or drag to upload two or more PDF files. You can add up to 20 files at once.

  2. 2

    Arrange the order

    Drag the file thumbnails into the order you want them to appear in the merged PDF.

  3. 3

    Merge and download

    Click Merge PDF. Download the single combined PDF when processing is complete.

About PDF merger

Merging multiple PDF files into one document is one of the most frequent document tasks in professional and academic settings. Whether you are assembling a report from separately authored sections, combining scanned forms, or packaging a set of attachments into a single file, DocumentFlipper makes the process fast and reliable.

You can upload up to 20 PDF files at once and drag them into exactly the order you need before merging. The tool combines all pages from each file in sequence, producing a single PDF with continuous page numbering. No content is altered — text, images, annotations, and form fields from every source file are preserved in the output.

Your files are processed on our secure server over an encrypted connection. All uploaded files and the merged output are automatically deleted within two hours. No account or registration is required.

Frequently asked questions

How many PDFs can I merge at once?
You can merge up to 20 PDF files in a single operation.
Can I change the order of files before merging?
Yes. Drag and drop the file thumbnails into the order you want before clicking Merge PDF.
Will bookmarks and annotations be kept?
Annotations such as highlights and comments are preserved. PDF bookmarks from source files may not be carried over to the merged document.
Is there a page limit for the merged PDF?
There is no hard page limit. However, very large merges (hundreds of pages) may take a few extra seconds to process.
How long are my files stored?
All uploaded files and the merged PDF are automatically deleted from our servers within two hours.