Merge PDF Files Online — Combine Multiple PDFs Into One_
Combine two or more PDF files into a single document in seconds. Drag them into order and merge — pages keep their full quality and their selectable text. Free, no upload, no watermark, no sign-up.
Guide — merge PDF files in under a minute
Drop two or more PDF files on the box, or click it to pick them. You can add more files at any time; they join the end of the list.
Drag files up or down the list. The list order is the page order of the result: the first file's pages come first.
Click × next to a file you added by mistake. Nothing is merged until you press the button.
Press Merge into one PDF. The progress bar shows which file is being added.
Check the page count and size, then save merged.pdf. Your original files are not changed.
How the merge works
Each page is moved into the new file as it is. Text stays text, vector graphics stay sharp at any zoom, and scanned images keep their original resolution.
- Text
- Still selectable and searchable
- Images
- Not re-compressed
- Size
- Roughly the sum of the input files
Files are not sorted by name or date for you. Scanner and camera file names rarely match the reading order, so the list starts in the order you added the files and you drag from there.
- Drag
- Move a file up or down the list
- ×
- Remove a file from the list
- Pages
- Inside each file the order stays as it was
A PDF can hold pages of different sizes. A4 portrait next to A3 landscape next to US Letter all stay exactly as they were; nothing is stretched or cropped to match.
- Per file
- Up to 200 MB
- Files
- No set limit; memory is the ceiling
- Encrypted
- Skipped, with a message naming the file
The merge runs in the browser tab with pdf-lib. Contracts, payslips and medical letters are never uploaded, stored or seen by anyone else.
- Account
- None needed
- Watermark
- None
- Offline
- Keeps working once the page has loaded
Merge PDF files online, without uploading them
Merge PDF combines two or more PDF files into one document, right in your browser. Drop the files in, drag them into order and download a single PDF. It is free, it adds no watermark, there is no daily limit and no account, and because the work happens on your own device, the files are never uploaded to a server.
The merge is lossless. Rather than printing every page again into a new file, it copies the existing pages across, so the result looks exactly like the originals and its text can still be selected, searched and copied.
How to combine PDF files into one
Add the files with the drop box or the file picker; on a phone you can pick them from Files or your downloads. Drag them into the order you want — the first file in the list becomes the first pages of the result — and press Merge into one PDF. When it is done you see how many files were merged, the total number of pages and the file size, and you can download merged.pdf. To merge in a different order, just drag and merge again; your source files are not touched.
Why the merged file is as big as the originals together
Merging adds; it does not compress. Every page is carried over at full quality, so three 4 MB files make a file of about 12 MB. That is what you want for scans and signed documents. If the result is too big to email, compress it afterwards with Compress PDF, or keep it searchable and send it in two parts with Split PDF.
What survives a merge, and what does not
Everything you see on the page survives: text, fonts, images, vector drawings and the page size of each page. Some document-level features do not. Bookmarks (the outline in the sidebar of a PDF reader) from the source files are not carried over, links that jump to another page inside a document may point to the wrong place once pages are renumbered, and fillable form fields can stop working. For a form, fill it in first with the PDF form filler and merge the filled copy.
Merging PDFs with photos or scans
This tool takes PDF files only. If some of what you want to combine are photos or screenshots, turn them into a PDF first with JPG to PDF, where you can choose A4, Letter or the image's own size, and then merge that PDF with the rest. A stack that was scanned in several batches works the same way: merge the batches in order, and if one batch came out upside down, fix it with Rotate PDF.
Common jobs
- Expense claims and tax returns: put a month of invoices or receipts in date order and send one attachment instead of fourteen. The text stays searchable, so an amount can be found later.
- Reports built by several people: a designed cover, a body exported from Word and an appendix from a spreadsheet, joined without losing the sharp logo or the selectable tables.
- Job and visa applications: a letter, a CV, diplomas and an ID scan as one file, when a portal only accepts a single upload.
- Contracts with annexes: the main agreement followed by its schedules, in the order they are referenced.
When a file will not merge
If a file is skipped with "cannot read PDF", it is almost always encrypted. That includes PDFs that open without a password but block editing or printing. Open it in a PDF reader and save or "print to PDF" an unprotected copy, then add that copy. A file above 200 MB is refused, and a very large batch can be slow on a phone, because everything is held in memory; merge in two rounds and then merge the two results. If the download does not start, check that the browser is not blocking downloads from the page.
Is it safe for confidential documents?
Yes, because the documents never leave your computer or phone. Online mergers usually upload your files to their server; here pdf-lib, an open-source library, does the merge inside the browser tab. You can verify it by turning off Wi-Fi after the page has loaded and merging anyway, or by watching the Network tab of your browser's developer tools. There is nothing to delete afterwards: closing the tab clears it.
More PDF tools
The tabs at the top of this page also split, compress, convert and reorganise PDFs, and the PDF tools page explains all six. To black out confidential lines before you share the merged file, use the PDF redactor.