Merge PDF Files Online — Free
Combine any number of PDF documents into a single file in seconds. Upload, reorder by dragging, and download — everything runs in your browser, nothing leaves your device.
- 1Upload two or more PDF files
- 2Drag to set the order you want
- 3Click "Merge Files" to download your combined PDF
Merge PDFs
Upload the PDF files you want to combine.
Drag & drop files here
or click to browse from your computer
Why use pdflu for this?
pdflu merges PDFs entirely in your browser — no file upload, no sign-up, no file size limit. Your documents never leave your device.
Unlike server-based tools, pdflu processes everything locally using pdf-lib, meaning your confidential or sensitive PDFs stay private every time.
Tips for best results
- You can merge unlimited PDFs in one go — just keep adding files
- Drag thumbnails to reorder files before merging
- All PDFs should ideally use the same page size for a cleaner result
- Password-protected PDFs must be unlocked first — use the Unlock PDF tool
- Larger PDFs take longer to merge; for very large files split them first then merge selected sections
Frequently Asked Questions
Can I merge more than 2 PDF files at once?
Yes — there is no limit on how many PDFs you can merge. Simply drop all your files onto the upload area at once or add them one by one, drag to reorder, and click Merge Files.
Will merging PDFs affect the quality of my documents?
No. pdflu copies pages from each PDF directly into the merged file without re-encoding or re-compressing anything. Text, images, and formatting are preserved exactly as they were in the originals.
How do I merge PDFs on iPhone or Android?
Open pdflu.com in your mobile browser (Chrome or Safari work best), tap the upload area, select your PDFs from your device storage, rearrange them, then tap Merge Files. No app needed.
Can I merge password-protected PDFs?
pdflu cannot read encrypted PDFs directly. Unlock each protected PDF first using the Unlock PDF tool, then merge the unlocked files.
Is there a file size limit for merging?
There is no hard limit set by pdflu, but very large files (over 100 MB) may be slow or run into browser memory limits. For best results, compress large PDFs first.