Guides

How to merge PDF files on any device without uploading

You can combine PDFs on a phone or computer without sending them to anyone's server. One method works the same everywhere, and Macs have two built-in options.

Published by ThatToolSite

Merge PDF joins files in your browser on a phone, tablet or computer. Nothing is uploaded, and there is no account or daily limit.

Merge PDFs

One method that works on every device

A merge tool that runs in the browser works the same in Safari on an iPhone, Chrome on Android, and Edge, Chrome or Firefox on a computer. The files are read and joined by your own device.

  1. Open Merge PDF and add your files. On a phone, tap to choose files from the Files app, iCloud Drive, Google Drive or your downloads. On a computer, drag them onto the page.
  2. Put them in order. Drag the files into the order you want. The first file becomes the first pages.
  3. Merge and download. On an iPhone the result goes to Downloads in the Files app, on Android to Downloads, and on a computer to your Downloads folder.

What each device has built in

DeviceBuilt-in way to mergeNotes
iPhone and iPadSometimes, in the Files appOn recent versions, selecting several files in Files may offer Create PDF in the More menu. The menu path varies by iOS version, and pages are joined in file-name order.
AndroidNot as standardSome phone makers’ file apps add PDF tools, but Android itself doesn’t include a PDF merger.
WindowsNoWindows can print one document to PDF, but it has no tool for joining existing PDFs.
MacYes, twoPreview and the Finder’s Create PDF quick action, below.

Where there’s nothing built in, the browser method above is the quickest option that doesn’t involve installing an app or uploading the files.

Mac: Preview and Finder

Preview

Preview saves changes automatically, so Apple suggests duplicating each PDF first (File > Duplicate) if you want to keep the originals.

  1. Open the PDFs in Preview. Then choose View > Thumbnails in each one to show the page sidebar.
  2. Drag pages across. Drag thumbnails from one file’s sidebar into the other’s, at the end or between pages. Command-click to pick pages that aren’t next to each other.
  3. Add a whole file at once. Drag the PDF’s icon from the Finder onto the sidebar of the open document.

Finder quick action

Select the files in the Finder, Control-click them and choose Quick Actions > Create PDF. Apple notes that the files appear in the order you selected them, so click them in the order you want.

Getting the page order right

  • Number the files first if a method sorts by name: “01 Cover letter.pdf”, “02 CV.pdf”. The leading zero matters because some apps sort “10” before “2”.
  • Fix pages after merging with Reorder PDF pages, which lets you drag single pages, not just whole files.
  • Check the first and last page of each original in the merged file. That’s where mistakes show up.

How to tell whether a merge tool uploads your files

Many free PDF websites send your files to their servers to do the work, then delete them later. For leases, medical letters or anything with an ID number, it’s worth checking first:

  • The airplane mode test. Load the page, switch off Wi-Fi and mobile data, then merge. A tool that works locally still works. One that uploads fails.
  • Watch for an upload bar that fills up before any processing starts.
  • Read the privacy page. “Files are deleted after one hour” means the files were on their server for that hour.

What merging can change

  • Digital signatures no longer validate once the document is changed, so merge before signing, or send signed files separately.
  • Fillable forms may lose their fields. Fill in and save forms before merging.
  • Password-protected files must be opened with the password before they can be merged.
  • Bookmarks and internal links (the clickable outline in the sidebar, or “see page 4” links) often don’t survive a merge. Check them if the document relies on them.
  • Very large scans on a phone can be slow, because your phone does all the work in its own memory. Close other tabs, or merge in two rounds.
  • Size adds up. The merged file is roughly the sum of the originals. If it’s too big to send, run it through Compress PDF.

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