Merge PDF files
Combine two or more PDFs into a single file. Reorder pages by dragging before you merge.
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Select PDF files
or drag and drop here
Accepted formats: PDF
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Quick facts
- What it does
- Combines two or more PDF files into a single PDF, in the order you arrange them.
- Input
- Output
- Processing
- In your browser
- Files uploaded?
- No
- Account required?
- No
- Best for
- Putting a set of documents into one file while keeping page order and bookmarks.
- Main limitation
- Very large sets are limited by how much memory the browser can allocate at once; merging hundreds of files can fail where merging ten will not.
How to use this tool
- Upload two or more PDF files (drag and drop or click to browse).
- Drag the file cards to set the order you want.
- Click "Merge PDF" to combine them.
- Download your combined PDF.
Why use iBuildPDF
Merging happens locally in your browser using open-source PDF libraries — your documents are never uploaded to a server, so there is nothing to wait on and nothing to worry about.
How it works
iBuildPDF reads each PDF's pages directly in your browser and writes them into one new document in the order you choose, preserving the original page content and quality.
Frequently asked questions
Is there a limit to how many PDFs I can merge?
No fixed file-count limit. Very large combined documents are limited only by your device's available memory, since merging runs in your browser.
Will merging reduce PDF quality?
No. Merging copies the original pages as-is; it does not re-compress or re-render them.
Do you keep a copy of my files?
No. Processing happens on your device, so your files are never sent to iBuildPDF's servers.
Does merging PDFs reduce quality?
No. Merging copies each page's original content — text, fonts and embedded images — into the new file without re-rendering or recompressing anything, so nothing loses sharpness. The combined file is roughly the sum of the originals, because merging does not compress. If the result is too large to email, run it through Compress PDF afterwards as a separate step.
Is there a limit to how many PDFs I can merge at once?
There is no fixed file or page limit, but everything happens in your browser's memory rather than on a server, so a very large batch — dozens of files, or a few thousand combined pages — can slow down or run out of memory on a phone or an older laptop. If a big merge stalls, doing it in two smaller passes almost always works.
Can I merge PDFs with different page sizes or orientations?
Yes. Every page keeps its own dimensions and orientation instead of being forced onto one uniform size, so a merged file can legitimately contain a mix of portrait, landscape, A4 and Letter pages. That is normal and displays correctly — PDF readers render each page at its own size, one after another.
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