How to merge PDF files
- Drag your PDF files into the box above, or click "Choose PDFs" and pick them from your computer or phone. You can keep adding files after the first batch.
- The order of the list is the order of the finished document. Use the arrow buttons, or drag a file by its handle, to rearrange. Remove anything you added by mistake with the cross.
- Optionally rename the output file and decide whether each source file should get a bookmark.
- Press "Merge PDFs". Depending on the total page count this takes a few seconds, and the progress bar shows which file is being processed.
- Press "Download PDF" to save the combined document. Your original files are never changed.
When you need to merge PDF files
The most common reason is paperwork. A job application portal that accepts a single attachment, a landlord who wants proof of income and ID in one email, a visa or school form that asks for "one PDF containing all supporting documents" — these all turn into the same chore of stitching separate files together. Merging your CV, cover letter and references into one tidy document means the recruiter opens one file instead of three and sees everything in the order you chose.
The second big use is archiving. Twelve monthly utility bills become a single yearly file; a scanned contract and its signed amendment stay together; chapters of a report written by different colleagues become one document you can number, print and send. Students merge a cover sheet, the main text and appendices before submitting coursework, and freelancers combine an invoice with its supporting receipts so accounting can approve it in one go.
Because the tool copies pages exactly as they are, nothing is redrawn or recompressed. Text stays selectable, images keep their original quality, and mixed page sizes such as Letter, A4, landscape and portrait remain as they were. When the bookmark option is on, every source file gets an entry in the document outline, which readers such as Adobe Acrobat, Chrome, Edge and macOS Preview show in their sidebars.
Tips for a clean result
Put the files in order before you press the button; reordering afterwards means merging again. Give the output a meaningful name such as "Jane-Smith-application.pdf" instead of "merged.pdf", because that is what the person on the other end will see. If your combined file ends up too large for an upload form or email limit, run it through our Compress PDF tool next. If you only need a few pages from a long document, use Split PDF first to extract them and merge those.
Password-protected PDFs cannot be merged, because the tool needs to read the pages. If a file is locked, open it in a viewer where you know the password, print it to PDF or save an unlocked copy, and add that copy instead. Files that only restrict printing or copying but open without a password usually merge without trouble. Scanned documents merge fine too, although a merge does not add a searchable text layer; that requires OCR, which this tool does not perform.
One limitation is worth knowing: interactive form fields and digital signatures cannot survive a merge, because a signature certifies one exact version of one exact file. A filled-in form keeps its appearance, but fields are no longer editable and a signed document will no longer validate. Keep signed originals separate and attach them as individual files when the recipient needs to verify them.
Why use this merger?
- Nothing is uploaded. The merge runs inside your browser with the open-source pdf-lib library. Contracts, IDs and tax documents stay on your device, and the page keeps working if you switch off your internet after loading it.
- No limits and no watermark. There is no cap on files, pages or daily use, and no account to create.
- Quality is untouched. Pages are copied, not re-rendered, so fonts, images and layout are identical to the originals.
- Works on phones. The layout adapts down to small screens, though a computer is faster for very large files.
Frequently asked questions
Are my PDFs uploaded to a server?
No. After the page has loaded, the whole merge happens on your device. You can verify this by turning off your connection and merging again; it still works.
How many PDF files can I merge at once?
There is no artificial limit. The only boundary is your browser memory: dozens of files with hundreds of pages merge comfortably on a normal computer. For archives larger than about 500 MB, merge in groups and then merge the results.
Will the merged file be bigger than the originals?
Usually it is about the sum of the inputs, occasionally a little smaller because shared fonts are stored once. If you need a smaller file for an email or upload form, use the Compress PDF tool afterwards.
How do I change the order of the pages?
Reorder the files in the list with the arrow buttons or by dragging the handle. To reorder pages inside a single file, extract them with Split PDF and merge them again in the order you want.
Can I merge password-protected PDFs?
Not directly. Remove the password in a program where you know it, save an unlocked copy and add that copy. This tool never tries to guess or bypass passwords.
Are form fields and signatures kept?
The visible content of filled forms is kept, but form fields become static and digital signatures stop validating. Keep signed originals as separate attachments.
Does it work on iPhone and Android?
Yes. Open the page in Safari or Chrome, choose the files from your device and merge. Large files are faster on a computer.
Is it really free?
Yes. There is no premium tier, no trial and no registration. The site is supported by unobtrusive ads that never sit next to the buttons.
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Need custom software or document workflows for your business? Get in touch with Bilişim Ajans.