Merge PDF Files
Merge PDF joins two or more PDF files into a single document, in the order you arrange them. Add the files, drag them into position, and download the result. Pages are copied rather than re-encoded, so text stays selectable and searchable and the quality is untouched.
Runs entirely in your browser — nothing you enter is uploaded.
PDFAbout merging PDFs
Merging copies each page object from your source files into a new document. Nothing is rasterised, re-compressed or redrawn, so a merged page is byte-for-byte the page you started with: text stays selectable, links inside a page keep working, and a scan does not pick up a second generation of compression artefacts. That is the difference between a tool that copies pages and one that prints them to images.
The output order is exactly the order of the list, so arrange the files before you merge rather than fixing it afterwards. There is no cap on file size or page count, because there is no server imposing one — the practical limit is your device's memory, since every file has to be held open at once while the new document is assembled. On a phone, a dozen large scans is a more realistic ceiling than a hundred.
Common questions
- Does merging PDFs reduce quality?
- No. Each page is copied as an object into the new document rather than re-encoded, so the result is identical to the source page. Text remains selectable and searchable, and images are not compressed a second time. Tools that lose quality do so because they rasterise each page into a picture first; this does not.
- Is there a limit on file size or the number of PDFs?
- No limit is imposed, because the merge runs on your device rather than on a server with quotas. The real constraint is memory: every file is held open while the merged document is built, so very large batches are bounded by your computer or phone rather than by us. If a merge fails on a big set, doing it in two passes usually works.
- What happens to a fillable PDF form when I merge it?
- The pages keep their appearance, but the fields stop being interactive. The catalogue that makes form fields fillable lives at the document level rather than on the page, so copying pages into a new document leaves it behind. If you need the entered values to survive, flatten the form first — most PDF viewers offer this as "print to PDF" or "flatten".
- Why will my password-protected PDF not load?
- Encrypted PDFs have to be decrypted before their pages can be read, and the library this tool uses deliberately does not implement decryption. Remove the password in the application that created the file, or in any PDF viewer that can save an unprotected copy, and the merge will work normally.