Merge PDF

How it works

This tool merges PDF files directly inside your browser tab — no server, no upload, no waiting in a queue. Each page from every file you drop is rendered as a thumbnail so you can see and rearrange the exact final order before anything is combined; the actual merge happens in a background Web Worker once you click Merge.

Drag any thumbnail to move it, or click the × in its corner to leave it out of the final PDF entirely. Pages from different source files can be freely interleaved — the order you see in the grid is exactly the order you get in the output, regardless of which original file each page came from. Your original files are never modified, and nothing you upload here ever leaves your device.

Combining PDFs like this is useful for turning a stack of individually-scanned pages into one document, assembling a set of invoices or reports into a single file for archiving or submission, joining separate chapters exported from a report generator, or simply putting a cover page in front of an existing PDF. Because merging happens page-by-page rather than file-by-file, you can build exactly the document you need in one pass instead of merging twice.

Under the hood, each page's content stream, fonts, and embedded images are copied byte-for-byte from the source PDF into the new one — nothing is rasterized, re-rendered, or recompressed. That means the merged file looks exactly as sharp as your originals, and any selectable or searchable text stays selectable and searchable in the result, unlike merging tools that flatten pages to images.

Limitations

Password-protected PDFs aren't supported yet — you'll get a clear message naming the file if one is detected, and the rest of your batch still merges normally. Bookmarks (the outline/table of contents) from the source files aren't preserved in the merged result, and form fields with matching names across different source PDFs may end up linked together, showing the same value in both places — both are limitations of how PDF merging works at a structural level, not something this tool chooses to skip. There's no limit on the number of files or pages you can merge; the only real ceiling is your browser's available memory, which comfortably handles documents into the hundreds of pages.

FAQ

Is this PDF merger really free?

Yes — completely free, with no file count or size limits, and no account required. Everything runs in your browser, so there's no server cost to recoup.

Can I reorder or remove pages before merging?

Yes — every page from every file you drop shows up as a thumbnail you can drag into any order, or remove entirely with the × button, before you click Merge.

Are bookmarks (the outline/table of contents) preserved?

No — merged PDFs don't carry over the original bookmarks from each source file. This is a real limitation of the underlying library, not something we chose to skip; if you rely on bookmarks, add them back afterward in a PDF editor.

What about PDF forms with fields of the same name in different files?

If two source PDFs both have a form field with the same name (for example, both have a field called "Name"), most PDF viewers will treat those as one logical field and show the same value in both places after merging. This is a known edge case with programmatic PDF merging in general, not specific to this tool.