How to Merge PDF Files on Android

Android has no built-in way to combine two PDFs, so merging on a phone always means bringing in an outside tool. If the documents are not sensitive, a free merge page in Chrome does it in about a minute; if they are, a free PDF app that works on the device keeps the files off anyone else’s server. The rest of this guide is about which trade-off you are actually making.

Android Itself Has No Merge Button#

Google’s help page for PDFs in Files by Google documents annotation only: pen, highlighter, erase, undo and redo, and showing or hiding your markup. The app’s full feature index covers unzipping, backing up to Drive, Safe folder, scanning, compressing and Quick Share, and lists no combine or merge anywhere in it. Chrome can create a PDF through More > Share > Print and then Save as PDF, but that print sheet handles the file you already opened, so it is not a way to staple several documents together.

Google Drive’s scanner is the native feature people often actually want. Open Drive, tap the camera button at the bottom right, capture the first page, then tap Add for each further page; you can save the finished scan as a PDF, and Google also ships a “Drive scan” home-screen widget. That builds one PDF out of camera captures. It is exactly right when your “files” are paper, and no help at all when they are already PDFs sitting in your Downloads folder.

Everything else is an outside tool. Here is the honest comparison before the details:

Route	Cost	Where the merge happens	The limit to know
PDF24 Merge PDF in Chrome	Free per PDF24’s page	PDF24’s servers	Files leave the phone; deleted after one hour
Adobe Merge PDF in Chrome	Free per Adobe’s page, no sign-in to merge	Adobe’s servers	Up to 100 files, 500 pages each, 1,500 pages total
PDFgear Android app	Free per the developer’s listing	On the phone; works offline	Vendor’s own description, not an independent test
Acrobat Reader “Combine Files”	Paid Acrobat subscription	Adobe’s cloud, sign-in required	Maximum 12 files, none shared for review
Google Drive scan	Free with a Google account	In the Drive app; the finished file saves to your Drive	Builds a PDF from camera pages; does not join existing PDFs
Termux plus qpdf	Free	Entirely on the phone	Command line; Termux’s own site offers it from F-Droid or GitHub

Merge in Chrome: PDF24 or Adobe#

PDF24’s Merge PDF tool is the cleanest free option here. Its own page says the tool is free of charge, needs no registration and no installation, and has no limits, while also stating plainly that the merge runs in the cloud on PDF24’s servers and that uploaded files are deleted from the server after one hour. Open it in Chrome, add the PDFs, put them in order, merge, download.

One thing to be clear about: there is no official PDF24 Android app. PDF24’s own homepage lists three products, and they are PDF24 Creator for Windows, the PDF24 Tools website, and PDF24 Fax. Several unrelated Play Store apps use the PDF24 name, so stay in the browser rather than going hunting for an app.

Adobe’s Merge PDF page is the other browser route. Adobe says it works in any supported mobile browser with no app to install, adds no watermark no matter how many files you combine, and lets you reorganize the files before merging without signing in, though you do need to sign in if you want to rearrange individual pages inside the merged document afterward. The published ceilings are 100 files, 500 pages per file, and 1,500 pages in the finished PDF. Uploaded files are deleted from Adobe’s servers unless you sign in and save them.

Both routes send your documents to a company’s server. For a rental application or a stack of receipts, that is a reasonable trade. For tax forms, medical paperwork, IDs or client documents, use one of the on-device routes below instead.

Merge on the Phone With a Free App#

When the files should not leave the device, the best-documented free candidate is PDFgear, from developer PDF GEAR TECH PTE. LTD. Its Play listing advertises “Merge & split PDFs freely” and appending pages from other PDF files to an existing one, and states that PDFgear provides free use for all functions without limits such as trial watermarks or page counts. The developer’s own Android page repeats that the app is free to use on Android with no hidden fees or advertisements, and says the app can function offline, so you can edit and manage PDFs without a connection. Carry two caveats with that: it is the vendor describing its own product rather than an independent test, and the same vendor notes there may be advanced options that could carry a charge in future.

The Play Store is full of near-identical “Merge PDF” apps with generic names and unverifiable ownership, and there is no honest way to recommend one sight unseen. Before you install anything you will hand private documents to, read the developer name and the Data safety section on the listing. Xodo, from Apryse Software, and iLovePDF both advertise merging on their Play listings, but neither listing states whether merging sits in the free tier or behind the subscription, so you generally find out only after installing.

Acrobat Reader’s Combine Files Is for Subscribers#

This is the point that catches people out. Adobe does advertise free PDF merging, and that is true of the browser tool above. Inside the Acrobat Reader app for Android it is a paid feature: Adobe’s Acrobat Reader help for Android says combining belongs to a paid Acrobat subscription, caps a single combine at 12 files, and requires you to be signed in to Document Cloud with an internet connection, because the combine runs as an online service rather than on the phone.

If you already pay for Acrobat, the flow is short. Long-press a file in the Home or Files list until a checkmark appears and keep tapping the other files you want, up to 12 and none of them shared for review. The alternative way in is the plus button, then Combine Files. Before you commit, you can drag the rows into a different order, remove anything you picked by mistake, and rename the output. Non-PDF files you include get converted to PDF during the combine. Adobe reworks this app’s interface regularly, so treat those as the two entry points rather than fixed icon positions.

Keeping the Files Off Anyone’s Server#

Two more routes are worth knowing when privacy matters more than convenience.

The first is your computer. If the phone is only where the files happen to live, merging on a PC and sending the result back beats fighting a small screen. Our guide to merging PDF files on a desktop covers the free tools, and moving files between Android and a PC covers getting them across in both directions.

The second is Termux, the terminal app for Android, which can run qpdf entirely on the device. Termux’s official site offers the app from GitHub and F-Droid. Once it is installed, qpdf is available through Termux’s package manager, and qpdf’s manual documents joining documents like this:

qpdf --empty --pages a.pdf b.pdf -- out.pdf

--empty starts from an empty PDF, --pages opens the page selection, and the bare -- closes it before the output filename. Nothing uploads and no account is involved. If you already run a home server, Stirling PDF is an open-source, self-hosted PDF toolkit whose operations include merge, reachable from Chrome on the phone; there is no Android app for it.

When a Merge Fails, and Where the File Went#

Symptom	Usual cause	What to do
The tool refuses one of the files	The PDF is encrypted or carries permission restrictions	Clear the security first, as in removing a password from a PDF; this needs the permissions (owner) password, not the open password
The merged file will not attach or upload	The combined PDF is simply too large	Shrink it using the steps in compressing a PDF file
Pages came out in the wrong order	Most routes lock the order in before the merge; Adobe’s online tool is the exception and only if you sign in	Redo the merge with the files dragged into place, or split the PDF and rebuild it
You cannot find the finished file	The app saved into its own folder	Search the filename in your phone’s file manager, which is My Files on Samsung, usually inside the Samsung folder, and Files by Google on Pixel

Adobe’s merge page claims formatting, fonts and layout survive the merge, but it says nothing about bookmarks, form fields or digital signatures, and neither do the other tools here. Open the finished document and look at it before you send it somewhere that matters.

Pick the route by what is in the files rather than by which app looks slickest. Ordinary paperwork can go through a browser tool in a minute. Anything carrying an account number, a signature or someone else’s personal details is worth the extra step of merging on the device or on your own computer, where nothing has to be uploaded at all.