Does merging PDFs reduce their quality?

No. The pages are copied as-is into the new document rather than being rendered and rebuilt, so nothing is re-compressed. Text remains real text, vector graphics stay resolution-independent, and embedded images keep their original data.

Are my files uploaded to a server?

No. The merge runs in your browser using your own processor, and there is no backend to send anything to. You can verify it rather than trust it: the page is served with a Content Security Policy containing connect-src self, which makes it structurally incapable of opening a connection to another origin. It is visible in the response headers.

Is there a limit on how many PDFs I can combine?

Docqify imposes no limit on file count, page count or file size. Because everything happens on your device, the real constraint is available memory — combining a few hundred megabytes at once will be slower on a phone than on a laptop.

Can I merge password-protected PDFs?

Not while they are still encrypted. If you add one, Docqify names the file and asks you to remove its password first, rather than producing a broken document or a generic error.

Does it work offline?

Yes. Once the page has loaded once, a service worker keeps it available with no connection at all. Since the merging never needed a network in the first place, an offline merge is identical to an online one.

Merge PDF without uploading

Combine PDFs into a single document. Your files never leave this device.

Nothing is uploaded
Works offline

Drop your PDFs here

Add two or more PDFs and they are combined in the order you set. Everything happens on this device — nothing is uploaded.

Merge PDF, done properly

Merging is a copy operation, not a conversion. Docqify reads the page objects out of each PDF and writes them into a new document unchanged, so text stays selectable, vectors stay sharp at any zoom, and images are never decoded and re-encoded. Resources shared between the files — a font used in all of them, for instance — are stored once rather than repeatedly, so the combined file is often slightly smaller than the sum of its parts rather than larger.

Files are read with the FileReader API and processed in memory. There is no server to upload them to, and the page ships a Content Security Policy that blocks connections to any other origin.
Drag the files into whatever order you want before merging. The order in the list is the order in the output.
Password-protected PDFs are detected and reported by name rather than failing silently, so you know which file to unlock first.
There is no page count or file size limit imposed by Docqify. The practical ceiling is your device memory, since every file has to be held in RAM at once.

Questions

Merge PDF — the details

PDF tools

Already have a PDF?

The same guarantee applies to every one of these: the file is opened by your browser, worked on there, and never sent anywhere.

Split PDFBreak a PDF into separate documents. Your file never leaves this device.

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