Merge PDF Files Online – Free and Private
Combine several PDF files into one document, in the order you choose.
🔒 Your file is processed inside your browser. It is never uploaded or saved.
What is Merge PDF?
Need one tidy document instead of a folder full of separate files? This merge tool joins two or more PDFs into a single file, keeping every page exactly as it was. You decide the order, press one button and download the result. Because the work happens inside your browser, a contract, a set of invoices or a scanned application never travels to a server on the way.
How to merge PDF files online
- Drop two or more PDF files onto the box, or click it and select them together. You can add more files later and they join the end of the list.
- Check the order of the list. Use the arrow buttons beside a file to move it up or down, and the cross to remove a file you added by mistake.
- Press the green Start button. Pages are copied one file after another into a new document, which takes a few seconds even for large files.
- Download merged.pdf and open it once to confirm the page order before you send or print it.
When Merge PDF is useful
Job and visa applications
Combine a cover letter, CV, certificates and ID scans into one file so the recipient opens a single attachment.
Invoices and receipts
Join a month of invoices or expense receipts into one document for your accountant or for a reimbursement claim.
Study notes and reports
Put chapters written in different programs, or lecture slides saved as PDF, into one file that is easy to print or share.
Contracts with attachments
Attach schedules, annexes and signature pages behind the main agreement so everything stays together.
Tips for better results
Rename your files with numbers such as 01-cover, 02-report and 03-annex before you add them. The list then starts in the right order and you only need to adjust a few items. If a PDF opens with a password, remove it first with the Unlock PDF tool. Merging keeps text selectable and does not re-compress pictures, so the combined file is roughly the sum of the originals. If the result is too large to email, run it through Compress PDF afterwards.
Why use PDFToolkit
When you merge PDF files online with PDFToolkit, the work stays on your own device. Your contracts, ID scans and invoices are processed in the browser and are never sent to a server.
- Private: no upload, nothing saved.
- Free: no sign-up, no daily limit and no watermark.
- Fast: no waiting for files to travel over the internet.
- Everywhere: Windows, Mac, Linux, Android and iPhone.
Frequently asked questions
Is there a limit on how many PDFs I can merge?
There is no fixed number of files. Each file can be up to 300 MB, and the total depends on the memory of your device, so a computer handles very large batches better than a phone.
Will the quality of my pages change when I merge PDF files?
No. Pages are copied across without being converted to pictures, so text stays sharp and selectable and images keep their original quality.
Can I change the page order after merging?
Yes. Open the merged file in the Organize PDF tool and type a new page order, or remove pages you do not need with Delete PDF Pages.
Do bookmarks and links survive the merge?
Page content and visible links are kept in most files, but bookmarks and the outline of each original are not carried into the new document.
Are my documents uploaded anywhere?
No. Merging runs in your browser and the files are never sent to a server. Closing the tab clears everything from memory.
Can I merge PDF files on my phone?
Yes, in any modern mobile browser. Select several files from your storage at once, or add them one at a time and reorder them with the arrows.