How to use it
- Press Choose files or drop two or more PDFs on the page. Each file gets a row with a preview of its first page, its page count and its size.
- Put the files in order with the ↑ ↓ buttons on each row, or drag a row with the mouse. The file at the top supplies the first pages of the new PDF.
- Leave Add a bookmark for each file ticked if you want a clickable list of the original files in the PDF's bookmarks panel.
- Check the page total under the list, press Merge PDFs, then Download to save merged.pdf.
What ends up in the merged file
Every page of every file is copied, in the order of the list, into one new PDF. The page count simply adds up: a 12-page contract, a 3-page annex and a 1-page cover give 16 pages.
Pages keep their own size and orientation. Merge an A4 report, a US Letter invoice and a landscape spreadsheet and you get exactly those three kinds of page, one after another. Nothing is scaled to match, so nothing is squeezed or cropped.
| Part of the PDF | In the merged file |
|---|---|
| Pages, text, pictures, page sizes | Kept exactly as they were, at the same quality |
| Highlights, comments, stamps and web links | Kept on their page |
| Bookmarks inside the original files | Not copied. The bookmark option adds one entry per file instead |
| Fillable form fields | What was typed usually stays visible, but the boxes can no longer be filled in |
| Digital signatures | No longer valid, because the merged file is a new document |
| Password or editing protection | The file can't be merged until the protection is removed |
A bookmark for each file
With Add a bookmark for each file ticked, the merged PDF gets one bookmark per original file. Each bookmark is named after the file, without ".pdf", and jumps to that file's first page. The PDF also asks readers to open with the bookmarks panel showing.
This makes a bundle of receipts, chapters or application documents easy to move around in. The option appears once there are two or more files in the list. Rename your files before you add them if you want tidy bookmarks: "Payslip March" reads better than "scan_0042".
Signed documents and fillable forms
A digital signature protects the exact version of the document that was signed. Adobe's validation guidance describes a signature as invalid when the revision it covers has been altered. Merging builds a brand-new file, so a signed contract inside a merged bundle will no longer show a valid signature. If someone needs to check the signature, send the signed PDF unchanged, alongside the bundle.
Fillable forms change too. The merged file keeps the look of each field, but the fields are no longer part of a working form, so nobody can type into them. Fill in and save each form first, then merge.
Password-protected PDFs
A PDF that asks for a password when it opens can't be read here, and its row says so. Some PDFs open without a password but block editing; those can't be merged either, and the merge stops with the same message.
Open the file in the app that made it, remove the protection and save a copy, then add that copy to the list. If the finished bundle needs a password, add it afterwards in an app that can encrypt PDFs.
Your files stay on your device
The merging is done by pdf-lib, an open-source PDF library, running inside your browser tab. Your PDFs are read from your device, combined in memory and handed back as a download; no copy goes to a server. That matters for the files people usually merge: bank statements, payslips, ID scans and contracts for a rental or loan application. See how you can check this yourself.
Questions
- Is there a limit on how many PDFs I can merge?
- No. There is no file or page limit, only your device's memory. If a phone struggles with a very large bundle, close other tabs or merge in two rounds: merge half the files, then merge that result with the rest.
- Will merging lower the quality or shrink the file?
- No. Pages are copied as they are, so text and pictures look exactly the same. The merged file is roughly the size of the originals added together. If it's too big for email, run it through Compress PDF.
- Can I merge only some pages of a file?
- This tool always takes whole files. Pull out the pages you need first with Split PDF, or merge everything and then delete pages with Organize PDF pages.
- Why do the pages in my merged PDF have different sizes?
- Because the originals did. Each page keeps its own size, so an A4 file and a US Letter file stay A4 and Letter. That's deliberate: resizing pages could crop or shrink their content.
- Why can't I press the merge button?
- It needs at least two PDFs that were read successfully. A row that shows an error (a damaged or protected file) doesn't count; remove it with × and add a working copy.
- Can I add photos to the bundle?
- Turn them into a PDF with JPG to PDF first, then add that PDF to the list here.