How to merge PDF files
Combine several PDFs into one tidy document, in exactly the order you want. It’s free, there’s no sign-up and no watermark, and because everything happens in your browser, your files are never uploaded anywhere.
- 1
Add your PDFs
Select several files at once, or drop them onto the box together. You can add more at any time with the “Add more PDFs” bar.
- 2
Put them in order
Each file appears as a card showing its first page, and the first card comes first. Drag cards into place with a mouse, or use the arrows under each card, which also work on phones and with a keyboard.
- 3
Check the preview
A preview shows every page of the merged PDF in its final order, colored by the file it comes from. Remove anything you added by mistake with the cross under its card.
- 4
Merge and download
Press Merge. Your combined document downloads straight away as merged.pdf, ready to rename, email or upload.
Everyday reasons to merge PDFs
Plenty of forms and inboxes want a single file, while your documents are scattered across several. Merging them saves the person on the other end from opening five attachments, and it means nothing gets left behind:
- Job and university applications: CV, cover letter, transcripts and certificates in one file.
- Expense claims: the claim form followed by every receipt.
- Contracts: the main agreement with its schedules and appendices.
- Scanned paperwork: pages you scanned in separate sessions, put back together.
- Bookkeeping: a month or a year of invoices for your accountant.
Tips for a tidy merged PDF
- Get the order right before you add files. Files you select together are added in the order your device lists them, so names that start with numbers (01-cv.pdf, 02-letter.pdf) save you reordering later.
- Fix sideways pages. If a scan came out sideways, run it through Rotate PDF first, or merge everything and then fix pages in Organize PDF, where you can also reorder individual pages across files.
- Drop blank pages. Double-sided scans often include empty backs. Delete PDF Pages removes them and makes the file smaller.
- Mixed page sizes are fine. A4 and US Letter pages, or portrait and landscape pages, keep their own sizes in the merged file.
- Rename before you send. “merged.pdf” tells nobody anything. Something like “smith-application-2026.pdf” helps reviewers who handle dozens of files a day.
What carries over into the merged file
Every page is copied exactly as it is: text stays selectable and searchable, images keep their resolution, and each page keeps its size and rotation. The merged file is usually about the same size as your original files added together.
Bookmarks and fillable form fields belong to each original document as a whole, so they aren’t combined into the new file. That’s typical for merge tools. If you need to fill in a form, complete it before you merge.
Private by design
Merging usually means handling several personal documents at once: identity papers, payslips, references. With PDFCocoon, every file is read and combined by your own browser, and the merged PDF is built on your device. Nothing is uploaded, stored or seen by us.
Prefer to use software you already have? Our guide on merging PDFs without Adobe Acrobat shows the built-in options on Mac, Windows and phones.
Frequently asked questions
How many PDFs can I merge at once?
There’s no fixed limit on the number of files. Each file can be up to 200 MB; with very large batches, speed depends on your device’s memory.
Can I change the order after adding files?
Yes. Drag the file cards, or use the arrow buttons under each card. The preview below always shows the exact page order of the merged PDF.
Can I merge password-protected PDFs?
No. Protected files are flagged as you add them. Open each one in your PDF reader with its password, save an unprotected copy, and add that instead.
What happens to pages of different sizes?
They keep their own size and orientation. An A4 report and a US Letter form can sit side by side in the merged PDF.
Will the merged file have a watermark?
No. PDFCocoon never adds watermarks, logos or extra pages to your documents.
Can I merge PDFs on my iPhone or Android phone?
Yes. Open this page in your phone’s browser, choose several PDFs from your Files app or downloads, arrange them with the arrow buttons and tap Merge.