Merge PDF Tool
Combine several PDF files into one document, in the order you choose. Nothing is uploaded.
Files to merge
Your merged PDF is ready
The download starts automatically. Use the button if it does not.
Runs in your browser. Your file is never uploaded.
How to merge PDF files
Drop the files onto the panel above, or tap it to browse. Each one is opened in the browser and listed with its page count, so you can see straight away that the right documents are in the job. Two files are the minimum; there is no maximum beyond what the device can hold in memory.
The merged document follows the order on screen, top to bottom. Use the arrows beside a file to move it, or the cross to drop it from the list. Add more files at any point by tapping the panel again — they join the end of the list rather than replacing what is already there.
Taking only part of a file
Every file has a pages box under its name. Leave it empty and the whole file goes in. Type a range and only those pages do. The box understands the shorthand people actually write: 1-3 for the first three pages, 2, 5, 9 for three separate pages, 4- for page four to the end, and last for the final page. The line under the box confirms what the range resolved to, so a typo shows up before you press merge rather than after.
What the merged file keeps
Pages are copied across whole. Text stays selectable, fonts stay embedded, images keep their original resolution and vector artwork stays vector. Nothing is rasterised or re-compressed, which is why the merged file is usually close to the sum of its inputs rather than noticeably larger or blurrier.
Where the work happens
This tool has no backend. The file is read with the browser's own file reader, combined with pdf-lib in the page, and handed back as a download built from memory. No copy is sent anywhere, none is stored, and there is nothing to delete afterwards.
That matters most for the documents people actually merge: contracts, invoices, medical letters, bank statements and scanned identity papers. It also means the tool keeps working with the network off once the page has loaded, and that a slow connection costs you nothing beyond the first load.
Practical limits
| Situation | What to expect |
|---|---|
| A handful of ordinary documents | Merges in well under a second on any current device. |
| Several hundred megabytes at once | Fine on a desktop. On a phone, merge in two or three passes instead. |
| Password protected file | Cannot be opened by any tool without the password. Remove it in your reader first. |
| Scanned PDF of many photographs | Merges normally, but the result is large because the images are large. Nothing is re-compressed. |
Questions
Are my PDF files uploaded to a server?
No. The files are read by your browser and combined there. This tool has no backend, so there is nothing for a file to be sent to, and the page keeps working after it has loaded even with the network switched off.
How many PDFs can I merge at once?
There is no fixed limit. The practical ceiling is the memory of the device: a desktop handles hundreds of megabytes comfortably, while an older phone is happier with a few files at a time. The tool reports progress as each file is added so a large job is visible rather than silent.
Can I merge only some pages from a file?
Yes. Each file in the list has a pages box. Leave it empty to take everything, or type a range such as 1-3, 8, 12- to take only those pages. The word last is understood too, so 5-last takes page five to the end.
Does merging reduce the quality of the pages?
No. Pages are copied across as they are, with their fonts, images and vector content intact. Nothing is re-rendered or re-compressed, so a page in the merged file is the same page it was in the original.
Why will my file not open?
The usual reason is a password. A PDF that asks for a password before it will display cannot be read by any tool without it; remove the password in your PDF reader and try again. A file that was only partly downloaded fails for the same reason a reader would refuse it.
What happens to bookmarks, links and form fields?
Page content, images and internal appearance are preserved. Document level structures such as the bookmark outline and form field values do not survive a merge, because they belong to the document rather than to the pages being copied. Flatten a form before merging if the values matter.
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