How to Merge PDF Files: Complete Guide

Need to combine multiple PDF files into one document? Whether you're merging reports, combining scanned pages, or creating a portfolio, this guide covers all the ways to merge PDFs.

Why Merge PDF Files?

Common reasons to combine PDFs include:

• Creating a single document from multiple scanned pages
• Combining chapters into one complete book or report
• Merging invoices or receipts for expense reports
• Assembling a portfolio from separate project files
• Combining signed pages with the original document
• Creating comprehensive presentations from multiple sources

Method 1: Online PDF Merger (Fastest)

The easiest way to merge PDFs is using a free online tool:

1. Go to Desi PDF Merge tool
2. Click "Select PDF Files" or drag and drop your files
3. Arrange files in your desired order by dragging
4. Click "Merge PDF"
5. Download your combined document

How to Arrange Pages Before Merging

When merging multiple files, you can:

• Reorder files: Drag and drop to change the sequence
• Remove files: Click the X to exclude a file
• Add more files: Upload additional PDFs at any time
• Rotate pages: Fix upside-down or sideways pages

Method 2: Using Adobe Acrobat

If you have Adobe Acrobat Pro:

1. Open Acrobat and go to Tools → Combine Files
2. Click "Add Files" and select your PDFs
3. Drag to reorder files as needed
4. Click "Combine"
5. Save the merged document

Method 3: Using Preview on Mac

Mac users have a built-in option:

1. Open the first PDF in Preview
2. Go to View → Thumbnails
3. Drag other PDFs into the thumbnail sidebar
4. Position pages where you want them
5. Export as PDF (File → Export as PDF)

Method 4: Using Microsoft Word

A workaround using Word:

1. Open Word and go to Insert → Object → Text from File
2. Select your first PDF
3. Repeat for additional PDFs
4. Save/Export as PDF

Note: This may affect formatting and works best with text-heavy documents.

Tips for Better Results

1. Check Page Sizes

If your PDFs have different page sizes, the merged document will have mixed sizes. Consider standardizing to A4 or Letter size first.

2. Maintain Bookmarks

Some merge tools preserve bookmarks from source files, creating a navigable table of contents in the final document.

3. Compress After Merging

Merged files can get large. After combining, use a PDF compressor to reduce the file size.

4. Add Page Numbers

For long documents, add page numbers after merging using a page number tool.

Merge vs. Insert

Understanding the difference:

For more precise control over page placement, use our Organize PDF tool.

Common Issues & Solutions

Merged PDF is too large

Compress the merged file using our compression tool. Or compress individual files before merging.

Pages are in wrong order

Use the drag-and-drop feature to reorder before merging. Or use Organize PDF to rearrange after merging.

Some pages are rotated wrong

Use Rotate PDF to fix orientation before or after merging.

Can't merge password-protected PDFs

First unlock the PDFs using our Unlock PDF tool (if you have the password).

Security Considerations

When using online PDF tools:

• Choose services that don't store your files (like Desi PDF)
• Check the privacy policy
• Avoid uploading highly sensitive documents to unknown services
• Consider desktop software for confidential documents

Frequently Asked Questions

Can I merge PDFs for free?

Yes! Desi PDF allows you to merge unlimited PDF files completely free of charge, with no watermarks or file size limits.

How many PDFs can I merge at once?

Most online tools (including Desi PDF) can handle dozens of files. The practical limit is usually browser memory for very large batches.

Will merging reduce quality?

No. Merging simply combines the files without re-encoding. Quality is preserved exactly as in the original files.

Can I merge different file types?

To merge Word docs, images, or other files with PDFs, first convert them to PDF using our conversion tools, then merge.