Merge PDF files
Combines several PDFs into one document without uploading them anywhere.
Drop the files, put them in order, press one button — and a single PDF comes back. The combining is done by your own browser, so contracts, statements and scans are never sent to anyone’s server.
Runs entirely in your browser. Your PDFs are never uploaded — the page fetches its own PDF library and nothing else, and your files are never among the requests.
How to use it
- Drop two or more PDFs onto the box above, or click it to choose files. You can add more later.
- Arrange them with the arrows — the top of the list becomes the front of the document. The cross removes a file.
- Press Merge into one PDF. The combined file downloads as merged.pdf.
What this tool does
Each file you add is opened right away, on your device, and its row shows the page count and size — so a wrong or broken file announces itself before you merge, not after. A password-protected PDF is refused with a clear note on its row; this tool does not try to get around encryption.
The merge itself copies every page of every readable file, in list order, into a fresh document. Pages are transplanted whole: text, images, vector graphics, form appearance — nothing is re-encoded or recompressed, so the quality of the output is exactly the quality of the input. A ten-page file plus a three-page file gives a thirteen-page file, front to back in the order you arranged.
Page geometry is preserved per page. If one source is A4 portrait and another is US Letter landscape, the merged document simply contains both kinds of pages, the way any PDF viewer expects. Nothing is scaled or cropped to force uniformity.
What does not carry over: bookmarks — the outline tree some PDFs show in a sidebar — and links that jump from one page to another inside a source file. Links pointing to websites usually keep working. If your workflow depends on a deep outline, rebuild it in a desktop editor after merging.
Order matters
The list is the document. Whatever sits at position one opens the merged file, and everything else follows in sequence, so the arrows on each row are the whole interface for structuring the output. The usual assemblies are simple: cover letter above the resume; invoice above the timesheets that justify it; chapters scanned as separate files stacked in reading order.
Two habits make this painless. First, add everything before you start sorting — rows keep their positions as new files land at the bottom of the list. Second, if you notice a missing file only after merging, there is no penalty: drop merged.pdf back into the tool together with the stray file, order the two rows, and merge again. Because pages are copied without recompression, a second pass does not degrade anything.
A note on what lands in the list: files arrive in the order your operating system hands them over, which is not always the order you selected them in the picker. Do not fight the picker — just drop everything in and read the rows top to bottom before pressing the button. Each row shows its position number, name, page count and size, so a stray draft version usually gives itself away by its page count before it can sneak into the final document.
If what you actually need is the reverse operation — pulling a few pages out rather than stacking files together — that is the Split PDF tool. The two are built to be used in tandem: split the pages you need from several documents, then merge the pieces in the right order.
Examples
| You have | You want | How |
|---|---|---|
| Cover letter.pdf + Resume.pdf | One application file | Letter first, resume second, Merge |
| Invoice.pdf + three receipts | One file for accounting | Invoice on top, receipts in date order |
| Contract.pdf + signed last page scan | Complete signed contract | Merge, then remove the unsigned page with Split PDF |
| Chapters 1–5 as separate PDFs | One manuscript | Add all five, arrange with arrows, Merge |
| A4 report + Letter appendix | One document | Just merge — each page keeps its own size |
What usually goes wrong
- A file shows “password-protected” on its row. Encrypted PDFs cannot be read without the password. Open the file in your PDF viewer, unlock it, save an unlocked copy and add that instead.
- The Merge button stays grey. It needs at least two readable files. A file with an error on its row does not count — remove or replace it.
- Bookmarks disappeared. Expected: outlines are not copied, only pages are. The visible content is untouched.
- A form stopped calculating. Interactive form logic can reference document-level structures that do not survive transplanting. The filled-in appearance of the fields stays visible, but live behaviour may not.
- Merging two 50 MB scans is slow on a phone. Everything happens in the device’s memory, and big scanned files are mostly images. It finishes — the progress line keeps counting files — but a laptop does it faster.
Doing it without this tool
macOS. Preview merges natively: open the first PDF, show the thumbnail sidebar, and drag the other files into it, then export. Free and offline, though the drag ordering gets fiddly past a few files.
Windows. There is no built-in merger. Acrobat does it on a paid plan, and most free desktop utilities wrap the same open-source engines this page uses — with an installer and, often, a watermark on the free tier.
Command line. With poppler installed, pdfunite a.pdf b.pdf out.pdf is instant. Ghostscript can do it too: gs -dBATCH -dNOPAUSE -sDEVICE=pdfwrite -sOutputFile=out.pdf a.pdf b.pdf — but note that Ghostscript re-encodes the file, which can change size and quality; pdfunite and this page do not.
Online merge services. The mainstream ones upload your documents to their servers, process them there, and delete them “within a few hours” per policy. For a rental contract or a bank statement, the upload itself is the problem. Here the files stay on your machine, full stop.
Privacy: your files never leave your browser
Everything — reading the files, counting pages, copying them into the new document, saving the result — happens in your browser’s memory on your own device. The only network request this page makes for the job is fetching its own PDF engine, a standard open-source library served from this site. Your documents are never in any request. You can verify that in one minute: open DevTools, switch to the Network tab, and merge something.
The files people merge are exactly the files that should not tour the internet: signed contracts, medical records, immigration paperwork, financial statements. A merge service asks you to trust its retention policy with those. This page has nothing to retain — close the tab and no trace of the file exists anywhere but your device.
Related tools
Frequently asked questions
No. The files are opened and combined by your own browser. The page fetches its own PDF library once, and your documents are never among the requests — you can watch the network panel to confirm.
No fixed quota. There is no server enforcing limits, so the only ceiling is your device’s memory. Files over 50 MB trigger a warning because merging them can be slow, but the tool still runs.
No watermark, ever. Pages are copied into the new document as they are — images and text are not re-encoded, so quality does not change.
No. An encrypted file is refused with a clear message on its row. Unlock it with the password in your PDF viewer first — this tool does not attempt to bypass protection.
Pages and everything visible on them survive. Bookmarks (the outline panel) do not carry over, and links that jump between pages may stop working. Links to websites usually keep working.
Yes. Every page keeps its own size and orientation, so an A4 page sits next to a US Letter page unchanged. Viewers handle mixed sizes fine.
Exactly the order of the list: all pages of the first file, then all pages of the second, and so on. Use the arrows on each row to rearrange before merging.