How to Combine Multiple PDFs Into One File

The fastest way to merge PDFs depends on what you have

You can combine multiple PDFs into a single file using free tools built into Windows and Mac, or through free online services. The method you choose depends on how many PDFs you need to merge, whether you want to keep them on your computer, and what operating system you use. Most people can finish this task in under five minutes.

If you have just two or three PDFs and want to keep everything local, your computer's built-in tools are the simplest route. If you have many PDFs or need to rearrange pages before merging, a free online tool like ILovePDF or Smallpdf handles that more easily. All three approaches produce a standard PDF that opens in any PDF reader.

Key Takeaways

Windows 10 and 11 can merge PDFs through File Explorer by printing to PDF, and Mac can do the same through Preview without any additional software.
Online tools like ILovePDF and Smallpdf let you upload multiple PDFs, rearrange pages, and download the merged file without installing anything.
The print-to-PDF method works on any computer but requires you to open each PDF separately and print it in order.
Online tools are faster if you need to reorder pages or if you have more than five PDFs to combine.

Merging PDFs on Windows using Print to PDF

Windows 10 and 11 have a built-in PDF printer that lets you combine files without downloading software. Open the first PDF you want to merge, then print it to a new PDF file. When you print the second PDF, you can append it to the first one instead of creating a separate file.

Here is the step-by-step process: Open your first PDF in any PDF reader (Adobe Reader, Microsoft Edge, or Windows Photos all work). Press Ctrl + P to open the print dialog. In the printer dropdown, select Print to PDF. Click the Print button and choose where to save the file — name it something like "merged.pdf". Open the second PDF you want to combine. Press Ctrl + P again, select Print to PDF, and this time look for an option that says Print to file or Append to existing PDF (the exact wording varies by reader). If that option does not appear, you will need to use the online method instead.

The limitation of this approach is that you cannot rearrange pages once they are merged. If you need to reorder content, use an online tool instead.

Merging PDFs on Mac using Preview

Mac's Preview application can combine PDFs without any additional software. Open Preview, then use the sidebar to add and arrange your PDF files in the order you want them.

Open the first PDF in Preview (right-click the file and select Open With > Preview). Click View in the menu bar and select Thumbnails to show the sidebar. In the sidebar, you will see thumbnails of all pages in the current PDF. Now drag and drop additional PDF files into this sidebar — Preview will add them to the end of the document. You can rearrange pages by dragging them within the sidebar. Once all PDFs are in the order you want, click File and select Export as PDF. Name your merged file and click Save.

This method is faster than the Windows print approach because you can see all pages at once and rearrange them before saving.

Using an online tool for more control

Free online PDF tools like ILovePDF, Smallpdf, and PDF Merge give you the most control over page order and let you see exactly what the final file will look like before you download it. These tools work on any computer with a web browser.

Go to ILovePDF.com (or Smallpdf.com) and look for the "Merge PDF" option. Click the button to upload files and select all the PDFs you want to combine at once. The tool will display thumbnails of every page from every file. Drag and drop pages to rearrange them if needed — you can move pages from different PDFs around each other. Once the order is correct, click the Merge PDF button. The tool will process the files and let you download the merged PDF to your computer.

The trade-off with online tools is that you are uploading your files to a third-party server. ILovePDF and Smallpdf both state they delete files after a few hours, but if your PDFs contain sensitive information, use the Windows or Mac method instead.

What to do if you have many PDFs

If you need to combine ten or more PDFs, an online tool is much faster than opening each file individually. Upload them all at once, arrange the pages in the preview, and download the result. The print-to-PDF method would require you to open and print each file separately, which takes significantly longer.

Some online tools also let you delete specific pages before merging, which is useful if some of your PDFs contain cover pages or blank pages you do not want in the final file. Check the tool's interface for a delete or remove option in the thumbnail view.

Troubleshooting common problems

If the print-to-PDF method does not show an "append" option, your PDF reader does not support that feature. Switch to Preview (on Mac) or use an online tool instead. If an online tool times out or fails to upload, your PDFs may be very large — try uploading them in smaller batches of three or four files at a time, then merge the resulting files together.

If the merged PDF opens but the pages are in the wrong order, you uploaded them in the wrong sequence. Most online tools let you download the file and try again without re-uploading everything. On Mac, you can also reopen the merged PDF in Preview, rearrange pages in the sidebar, and export it again.

Frequently Asked Questions

Can I merge PDFs on my phone?

Yes, but it is slower than using a computer. On iPhone, use the Files app to open PDFs in iBooks or a PDF reader, though most phone apps do not have a merge feature built in. Android has similar limitations. For phone users, uploading to an online tool like ILovePDF through your phone's browser is usually the easiest approach.

Will merging PDFs reduce the quality?

No. Merging is a file-organization operation that does not re-compress or alter the content of the PDFs. The merged file will have the same quality as the originals.

What if one of my PDFs is password-protected?

You will need to remove the password before merging. Most online PDF tools have an "unlock PDF" feature separate from the merge tool. Unlock the file first, then use the merge tool. On Windows or Mac, you may not be able to print a password-protected PDF at all until you unlock it.

Can I merge PDFs and delete pages at the same time?

Online tools like ILovePDF and Smallpdf let you delete pages in the preview before merging. The Windows print method and Mac Preview method do not have a delete option — you would need to delete pages from individual PDFs before merging, or delete them from the merged file afterward using Preview or Adobe Reader.

Is there a limit to how many PDFs I can merge?

Online tools typically allow between 20 and 100 files per merge, depending on the service. If you have more than that, merge them in batches — combine the first 20, then merge that result with the next batch. The Windows and Mac methods have no hard limit but become impractical after five or six files.

This guide is for general information only and is not medical, financial, legal, or other professional advice. For decisions specific to your situation, consult a qualified professional. See our Editorial Policy.