PDF tool
Merge PDF files
Put several PDFs together into one, in whatever order you arrange them. Pages are copied across exactly as they are — nothing is re-rendered, so text stays selectable and file size stays sensible. The documents never leave your browser.
- 100% free
- No signup
- Never uploaded
Drop your files here
or click to browse from your device
Supports PDF · Max 100 MB per file · Up to 5,000 pages
- Secure & privateYour files are never shared
- Lightning fastMost images in under a second
- High qualitymozjpeg and libvips under the hood
- Works everywhereAny device, any browser
Output quality
Nothing is re-encoded. Pages move across as complete objects, carrying their fonts, embedded images and vector artwork with them, so a merged page is byte-for-byte as good as it was in its original file. Expect the result to be close to the sum of the inputs; it is often very slightly smaller, because fonts used by more than one document only need storing once. What does not survive is the bookmark outline and any form field structure — if the source files were fillable forms, merge them and you will keep the appearance but lose the fields.
See what this tool actually did to real files — median size change, speed and sample size, published whichever way the numbers fall.
Privacy: this tool does not upload your file
The file is never sent anywhere
This tool is JavaScript running in your tab. Your document is read from your disk into browser memory and never transmitted — not to us, not to anyone. It handles files up to 100 MB and 5,000 pages.
You can check this yourself
Load this page, turn off your internet connection, and run the tool. It still works. That is not a promise about our conduct — it is something you can verify in ten seconds.
Nothing to delete afterwards
There is no upload, no job record and no copy on any server, so there is no retention period. Close the tab and the working copy is gone with it.
No third parties involved
The PDF engine and its fonts are served from this domain rather than a public CDN, so no outside company sees that you used this page, or when.
Input, output and limits
Every figure below is read from the same configuration the server enforces, so this page cannot promise a limit the system will refuse.
- Input formats
- application/pdf
- Output format
- application/pdf
- Maximum file size
- 100 MB per file
- Maximum pages
- 5,000 per run
- Multiple files
- Yes — several files combined into one result
- Price
- Free, with no account and no watermark
- Processing
- Inside your browser — the file is never uploaded
- Engine
- pdf-lib, running inside your browser
- File retention
- None — nothing is uploaded, so there is nothing to keep or delete
Common use cases
Assembling an application from separate documents
Passport scan, bank statement, employment letter — each arrives as its own PDF and the form wants one file. Ordering matters here, and it is the thing people most often get wrong.
Putting scanned pages back together
Document feeders often produce one file per batch. Merging restores a single document without rescanning anything.
Combining a report with its appendices
Body, charts and raw data usually come out of different programs. One PDF means the reader gets everything in the right order without juggling attachments.
Troubleshooting
- The pages ended up in the wrong order
- The order in the list is the order used. Alphabetical sorting puts 10 before 2 — check the numbers beside each file before merging, and use the arrows to correct them.
- One of the files was refused as encrypted
- PDFs with password protection cannot be edited safely, including files that open normally but block printing or copying. The protection has to be removed first — and be aware that a file which merely opens without a prompt can still be encrypted.
- The bookmarks are gone
- The outline tree is not carried across by the merge. The pages and their internal links are all intact; only the sidebar navigation needs rebuilding.
- The browser ran out of memory
- Everything is held in the tab, so a very large set can exceed what one tab is allowed. Merge in two batches, then merge those two results.
Something else went wrong? Tell us what happened — a person reads every report, and that is how this list gets longer.
Frequently asked questions
Browse pdf toolsDoes merging reduce quality?
No. Pages are copied from one document into another at the object level, which means the text, fonts, images and vector drawings arrive unchanged. The merged file is roughly the sum of the originals — there is no re-encoding step to lose anything in.
Can I control the order?
Yes, and it is worth checking before you run it. Files come in whatever order your system provides, which is usually alphabetical — so "Chapter 10" sorts before "Chapter 2". Arrows beside each file move it up or down, and the number on the left is the position it will take.
Are bookmarks and links kept?
Links inside a page survive, but the document outline — the bookmark tree in the sidebar — does not carry across. That is a limitation of the library doing the copying. Page content itself is unaffected.
Is there a limit on how many files I can merge?
Up to 5,000 pages in total, and 100 MB per file. Because everything runs in your browser tab, memory is usually the real limit before either of those. If a very large batch fails, merge in two halves and then merge the halves.
Where does my file go when I use this tool?
Nowhere. This tool is JavaScript that runs inside your browser tab, so the file is read straight from your disk into memory on your own device and never sent to us. There is no upload, no job record and no copy to delete afterwards — close the tab and the working copy goes with it. You can confirm this yourself: load the page, disconnect from the internet, and the tool still works. It handles files up to 100 MB and 5,000 pages, and those limits come from what one browser tab can hold rather than from anything on our side.