How many PDFs can I merge?

There is no fixed limit — you can merge as many PDFs as your browser memory can hold (typically dozens of large files on modern devices).

Will the bookmarks and links be preserved?

Page content, text and images are preserved exactly. Some interactive features like form fields and bookmarks may not carry over for complex documents.

Are my files uploaded anywhere?

No. Merging happens entirely inside your browser using the open-source pdf-lib library. Files never leave your device.

Can I reorder pages before merging?

Yes. Drag any file in the list to change its position before clicking Merge.

Merge PDF

Combine multiple PDF files into one document. Drag to reorder, then download — everything runs in your browser.

Drop PDFs to merge

or click to browse your computer

Accepted: PDF · Files stay on your device

How to merge pdf

1
Drop or pick the PDF files you want to combine.
2
Drag any file up or down to set the page order.
3
Click Merge — your combined PDF downloads instantly.

Understanding merge pdf

Merging is a structural operation, not a re-render: the pages of every source file are copied into a single new document with their fonts, vector paths and embedded images untouched. Nothing is re-compressed, so text stays selectable and print quality is identical to the originals.

Because each source keeps its own page geometry, a merged file can legitimately contain a mix of A4 portrait, A4 landscape and US Letter pages. Most viewers and printers handle this fine, but if the result is going to a print shop it is worth normalising the page sizes upstream before merging.

The whole operation runs in your browser through pdf-lib. Files are read with the File API, assembled in memory and handed back as a Blob download, so a confidential contract never leaves the machine it was opened on.

When you would use it

—Bundling a month of supplier invoices into one file for your accountant.
—Assembling a tender response from separately written sections.
—Combining scanned ID pages, proof of address and a signed form into a single application attachment.
—Turning a set of exported chapter PDFs back into one continuous manuscript.

Practical tips

Name your files 01-, 02-, 03- before selecting them: most browsers return files in the order you picked them, and a numeric prefix makes mistakes obvious.
Merging is a good moment to drop cover pages you no longer need — remove them first with Remove Pages so the final file has no dead sheets.
If a source PDF opens with a password prompt, unlock it before merging; encrypted content cannot be copied into a new document.

Troubleshooting

The merge stalls on very large files: Everything happens in your device's RAM. Merge in two passes — combine half the files, download the result, then merge the two halves.
Pages appear rotated in the output: The rotation flag travels with each page. Fix the offending source with Rotate PDF, then merge again.

Frequently asked questions

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