How to Combine PDFs Into One File on Windows, Mac and Online

To combine two or more PDFs into one file, add them to a merge tool, drag them into the order you want and save a single PDF. On a Mac, Finder and Preview can do this without extra software; on a Windows PC with no PDF program installed, a free browser tool is the quickest route.

The request comes in many forms: "put these PDFs into one", "add two PDFs together", "attach everything as a single file". The job is the same each time. Pages from several files go into one new file, in an order you control, without changing how the pages look. This guide shows how to do it on a computer step by step, which built-in options exist on Mac and Windows, and how to fix the usual problems, such as a locked file or pages in the wrong order.

Key takeaways

• Merging copies pages into a new PDF as they are, so text and images keep their quality.
• Siliph's Merge PDF is free with no account, takes up to 50 files and 2 GB per task, and accepts images and Word, Excel or PowerPoint files next to PDFs.
• On a Mac, Finder's Create PDF quick action combines files, and Apple notes that "The files appear in the PDF in the same order that you select them" (Apple).
• Preview on a Mac saves changes automatically, so duplicate the originals before you combine them there.
• For merging on a phone, see our guide to merging PDFs on iPhone and Android without an app.

How to combine PDFs into one with Siliph

Merge PDF works in Chrome, Edge, Firefox and Safari on Windows, Mac, Linux and Chromebook.

1. Open Merge PDF and click Choose files to merge, or drag the files from a folder into the drop zone. You can add PDFs, JPG and PNG images, and Word, Excel or PowerPoint documents: up to 50 files and 2 GB per task.
2. Each file appears as a card with a first-page thumbnail, its page count and its size. Drag the cards until the numbered badges match the order you want. Use Add files to bring in something you missed, or Remove file to drop one.
3. If you need only some pages, switch from Merge files to Merge pages. Every page of every file then appears as its own thumbnail, so you can remove pages or move them between files. Reset puts everything back.
4. Click Merge PDF. When the combined file is ready, download it.
5. Open the result and scroll through it once, checking the order and that no page is missing.

Small sets of PDFs and images are merged in your browser. Office files, and larger sets, go over an encrypted upload, where Word, Excel and PowerPoint files of up to 100 MB are converted to PDF in their place in the order. Files on Siliph's servers are processed with no human access and deleted within 2 hours.

How to combine PDFs on a Mac without extra software

Finder: select and create

Apple's steps: in a Finder window, select the files, then "Control-click the selected files, then choose Quick Actions > Create PDF." Apple adds that "The files appear in the PDF in the same order that you select them" and that the new file gets "a name similar to the first file you selected" (Apple). Click the files in the order you want them, holding Command, before you run the quick action.

Preview: drag pages between files

Preview can "merge the entire contents of two or more PDFs". Open the PDFs, choose View > Thumbnails, and drag thumbnails from one sidebar into the other. To add a whole file, Apple suggests you "drag the PDF icon from the Finder to the sidebar of an open document" (Apple). Apple's warning is worth following: "Changes you make to a Preview document are saved automatically", so choose File > Duplicate first if you want to keep the originals.

How to combine PDFs on a Windows PC

If your PC has a full PDF program installed, it will usually have a combine or merge command. If it does not, a browser tool does the job without installing anything. Open Merge PDF in Edge or Chrome, drag the files in from File Explorer, set the order and download the result.

Microsoft Word is not a good merge tool. Opening a PDF in Word converts it, and Microsoft notes that "lines and pages may break at different locations" compared with the original (Microsoft Support). Merge the PDFs as PDFs, so each page stays exactly as it was.

Adobe also offers a free online merge tool. Adobe says it combines "up to 100 files, with each individual file limited to 500 pages", into a merged document of "up to 1,500 pages", and that files are "deleted permanently unless you sign in and save them" (Adobe).

Combining PDFs on a phone

On an iPhone running iOS 26 or later, Apple's Preview app can add a file into an open PDF: touch and hold a thumbnail and "Tap Insert from File" (Apple iPhone User Guide). On Android, and for more than two or three files on any phone, Merge PDF in the browser is quicker. Our phone merging guide walks through both platforms.

Getting the order right

Merge tools follow your order exactly, so mistakes come through exactly too. Three habits help:

• Name files before you start. "01-cover-letter.pdf", "02-passport.pdf" and "03-degree.pdf" sort themselves and are easy to place on the cards.
• Follow the reader's order. For most applications that is the form or cover letter first, then identity documents, qualifications, supporting evidence, and signed declarations last.
• Interleave double-sided scans with the right tool. If a single-sided scanner gave you one PDF of front pages and another of back pages, use Alternate & Mix. It takes page 1 of each file, then page 2, and so on, and can reverse the second file when the backs were scanned last page first.

Common problems and fixes

After merging, Add Page Numbers gives the bundle one continuous sequence, which helps when someone refers to "page 12" in a call. If the combined file must fit an upload limit, our guide on compressing a PDF to a specific size explains how to hit an exact number.

Frequently asked questions

How do I combine 2 PDFs into 1 for free?

Open Merge PDF, add both files, drag them into the right order and click Merge PDF, then download the result. It is free with no account. On a Mac you can also select both files in Finder and choose Quick Actions > Create PDF.

Does merging PDFs reduce quality?

No. Merging copies each page into the new file as it is, so text, fonts and images look exactly as they did. Quality only changes if you compress the merged file afterwards.

Can I merge PDFs with Word documents or images?

Yes. Merge PDF accepts JPG and PNG images and Word, Excel and PowerPoint files alongside PDFs. Images become pages, and Office files of up to 100 MB are converted to PDF in the position you give them.

How do I put multiple PDFs into one in a specific order?

Drag the file cards until the numbered badges match the order you want. For page-level control, switch to Merge pages and drag individual pages. In Finder on a Mac, select the files in the order they should appear.

Can I merge PDFs on Windows without Adobe Acrobat?

Yes. A browser tool works on any Windows PC without installing software. Open Merge PDF in Edge or Chrome, drag the files in from File Explorer, arrange them and download the combined PDF.