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Merge PDF

To merge PDFs, add the files, drag them into the order you want and press Merge — the combined PDF downloads straight away. Pages are copied as they are, so text stays selectable and images are not re-compressed. Everything runs in your browser, with no upload, no sign-up and no fixed limit on the number of files.

Files never leave your device

Updated

How to use Merge PDF

  1. 1Drop your PDF files onto the upload area, or click it to browse your device.
  2. 2Drag the arrows beside each file to put them in the order you want them merged.
  3. 3Add more files at any point — they are appended to the end of the list.
  4. 4Press Merge PDFs, then download the combined document.

How it works

Merging does not re-render or re-compress anything. Each source document is parsed, its page objects are copied across with their fonts and images intact, and they are written into a new PDF in the order you set. Text stays selectable and image quality is unchanged.

The file is read into your browser's memory, changed there, and handed straight back to you. Nothing is uploaded, so there is no queue and no copy sitting on a server afterwards.

Because the whole job happens in memory, the practical limit is your device's available RAM rather than an upload cap. Very large scanned documents on an older phone are the one case where you may want to merge in two smaller batches.

Worked example

Sending a single application pack instead of four separate attachments

  1. Add cover-letter.pdf, cv.pdf, references.pdf and portfolio.pdf.
  2. Move cover-letter.pdf to the top so it opens first.
  3. Merge and download application-pack.pdf.

Result: One 12-page PDF with the pages in exactly the order you arranged them.

Tips and common mistakes

  • Turn sideways pages upright and delete blank pages before you merge. A problem page is much easier to fix in its own small file.
  • Name the files with numbers in front — 01-cover, 02-cv, 03-references — so the order is easy to check at a glance.
  • Flatten any filled-in forms first. Form fields are not carried into the merged file, but flattened answers are part of the page and are.
  • Open the result and check that its page count equals the sum of the originals before you send it.

Frequently asked questions

Is there a limit on how many PDFs I can merge?
There is no fixed limit. Everything runs on your own machine, so the ceiling is how much memory your browser has available. Merging dozens of ordinary text PDFs is fine; a hundred large scanned documents at once may be slow on a phone.
Will merging reduce the quality of my PDFs?
No. Pages are copied across as-is rather than re-rendered, so text, vector graphics and embedded images come through untouched.
Are my files uploaded anywhere?
No. The merge happens inside the browser tab. You can confirm this by opening your browser's network tools — no request carries your document.
Can I merge password-protected PDFs?
Only if the password has already been removed. Encrypted PDFs cannot be read without the password, so the tool will report that the file could not be processed.
Does the merged file keep bookmarks and form fields?
Page content, text and images are preserved. Document-level features such as bookmarks, form fields and annotations are not carried across, because they are attached to the original document structure rather than to individual pages.
Can I merge PDFs on my phone?
Yes. The merge runs in the phone's browser like it does on a computer. Very large scanned documents use a lot of memory, so on an older phone merge them in two batches.
How do I merge only some pages from each file?
Take the pages you want out of each document first with Extract PDF Pages, then merge the smaller files.
Can I combine photos and PDFs into one file?
Turn the photos into a PDF first with JPG to PDF, then merge that file with the others.
Why are the pages in my merged PDF different sizes?
Merging keeps every page exactly as it was, so an A4 scan next to a US Letter page stays a different size. To make them uniform, run the merged file through the PDF Page Size Converter and choose one size with Scale to fit.
An upload portal rejected my merged PDF. What should I check?
Size is only one rule. Check that the file has no password, that form fields are flattened, that the page count and page size match the instructions, and that the file name uses plain letters, numbers and hyphens.
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