📑 PDF300
Merge PDF files into one
Pick the PDFs, put them in the order you want, and get a single file back. Everything happens inside this page — the files are never sent anywhere.
Open the toolHow it works
- Add your filesDrop the PDFs onto the page, or click to pick them. Two or more.
- Put them in orderDrag a file to move it. The order on screen is the order in the merged file.
- DownloadPress Merge. The combined PDF is saved straight to your device.
Questions
No. Merging runs in your browser using JavaScript. Nothing is sent over the network, so the tool also works with the page open and the network off.
No watermark, and no sign-up. The practical limit is your device memory — large scanned files use more of it.
Guide: doing it well
When merging helps
Many application forms have a single upload slot for "supporting documents". Visa applications, university admissions, grant proposals and job portals all do this. Sending five separate files is not an option, and sending them in the wrong order makes the reader work harder. Merging also helps with email: one attachment named clearly is easier to file than six named scan0001.pdf to scan0006.pdf.
Step by step
- Collect every file first.Put them in one folder so nothing gets left out. If some of them are photos, turn them into a PDF with Image to PDF before merging.
- Add them to the Merge tool.You can select several at once or drop them in.
- Set the order with the ▲▼ buttons.The list top to bottom becomes page order in the merged file.
- Name the output.Change merged.pdf to something the reader will recognise, such as Kim_Minjun_visa_documents.pdf.
- Open the result and page through it.Check that the page count is the sum of the parts and that nothing is sideways.
Getting the order right
If the form lists required documents, follow its order exactly. If it does not, a sensible default is: the application form or cover letter, identity documents, then evidence in the order it is referred to. Put signed pages where the reader expects them, not at the end. Our guide on merging documents for applications goes through this in more detail.
Size
Merging does not compress anything — the result is roughly the sum of the inputs. If the merged file is over the limit, compress it afterwards with Compress to target size, or compress only the heaviest part (usually a scan) before merging so the text documents stay sharp.
Privacy
Merging runs entirely in your browser with pdf-lib. The files are read from your disk into this tab and the new file is written back to your disk. Nothing is sent over the network, so you can load the page, disconnect, and it still works.
Common problems
One file will not load. It is probably password-protected. Remove the password with the password removal tool (you need to know it), then merge.
Bookmarks disappeared. Pages are copied into a new document, and the bookmark list (outline) of the source files is not carried over. Page content, links inside pages and images are kept.
Pages are the wrong way round. Fix them after merging with Rotate & reorder.
More questions
There is no fixed number. The practical limit is your device's memory; dozens of ordinary PDFs are fine.
Split out the pages you need first with the Split tool, then merge the pieces.
No. Pages are copied as they are, without re-encoding.
Convert them to PDF first with the Office to PDF tool, then merge.
No watermark and no sign-up.