PDF Merge

Combine multiple PDF files into one — drag to reorder, set custom page ranges per file, add blank separators and choose your output options. 100% in-browser — no upload, no size limit.

Unlimited Files Drag to Reorder Page Ranges No Upload

Drop PDF files here or click to browse

Add multiple PDFs — drag to reorder — merge into one

📄 + 📄 + 📄 → ✅ One PDF
Files to Merge
0 files · 0 pages
Merge Options
Page Ranges
Output
Separator Between Files
None
Pages flow continuously
Blank Page
Add blank between each
Odd Align
Pad to odd page count
Options
Preserve Bookmarks
Merge PDF outlines
Preserve Metadata
Keep author, title info
Reverse Order
Last file becomes first
Skip Duplicates
Remove duplicate files
Page Ranges Per File (optional)
Leave blank to include all pages. Enter a range like 1-5 or specific pages like 1,3,5 to include only those pages from each file.
Add files first to configure per-file page ranges.
Output Filename
Filename (without .pdf)
Output Options
Page Order
Page Numbering
Merging PDFs…
Merge PDFs
Upload two or more PDFs, drag to set the order, then click Merge — one combined PDF ready to download instantly.
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Drag to reorder — use the ⠿ handle on each file row to drag it up or down. The merge follows the exact order shown in the list.
Page Ranges — include only selected pages from each file (e.g. 1-3, 5) using the Page Ranges tab. Leave blank to include all pages.
100% private — PDF-lib.js runs entirely in your browser. No file ever leaves your device — no server, no upload, no size limit.

How to Merge PDFs

1

Add PDFs

Drop multiple PDF files or click to browse. Add as many files as you need — there's no limit.

2

Set Order

Drag the ⠿ handle to reorder files. Use ↑ ↓ buttons or the Move Up/Down icons for precise control.

3

Configure

Set separators, page ranges per file, and output filename in the options tabs.

4

Download

Click Merge PDFs — PDF-lib combines everything in-browser and downloads the result instantly.

Frequently Asked Questions

Can I merge more than 2 PDFs at once?
Yes — there is no limit to how many PDFs you can merge. Add as many files as you want using the drop zone or the "Add More" button. Each file appears as a row that you can drag to reorder before merging.
How do I change the order of files?
Drag the ⠿ dot-grid handle on the left of each file row to reposition it. You can also use the ↑ and ↓ arrow buttons on the right of each row for precise one-step movement. The merge follows the exact list order.
Can I include only some pages from each file?
Yes. Open the "Page Ranges" tab and set a range (e.g. 1-5 or 1,3,7) for each file individually. Leave the field blank to include all pages from that file. This lets you cherry-pick exactly which pages contribute to the merged output.
What does "Odd Align" separator do?
If a file ends on an even page, Odd Align inserts one blank page so the next file always starts on an odd (right-hand) page. This is the standard technique for double-sided printed documents where each new section must begin on the right.
Is my PDF uploaded to a server?
Never. PDF-lib.js runs entirely in your browser — all files are read locally, merged in memory, and downloaded without touching any server. Your files stay completely private on your device at all times.
Does merging affect PDF quality?
No. PDF-lib copies the raw page content streams and resource dictionaries directly into the merged document. There is no re-rendering, re-encoding or recompression — every page in the output is bit-for-bit identical to the original.
No upload · No server · PDF-lib.js in-browser · Zero quality loss · Free forever · Pdf Pixy