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Merge PDF files online

Combine PDFs into one file in seconds.

Max file size: 60MB. Files are stored temporarily for processing and deleted on scheduled cleanup (typically within 12 hours).

Merge PDFs online (complete guide)

Merging PDF files is the fastest way to turn multiple documents into a single, shareable file: contract + annexes, invoices + receipts, or scanned pages from different sources. The merge itself is simple, but the best result comes from a clean workflow: prepare order → merge → verify → optimize size → protect (optional).

1) Prepare the correct order

Most merge mistakes are order mistakes. Before uploading, decide the final sequence. If your files are named inconsistently, rename them locally (e.g., 01-cover.pdf, 02-main.pdf, 03-annex.pdf). This makes the upload order obvious and prevents rework.

2) Merge the PDFs

Upload at least two PDF files and click Process. The tool produces one merged PDF. After download, do a quick spot-check: scroll to the boundaries where one document ends and the next begins. This catches missing pages or swapped order early.

3) If the merged PDF is too large, optimize it

Large merged PDFs are usually large because one of the inputs contains high-resolution images or scanned pages. After merging, run Compress PDF (start with Medium). For scanned documents, converting to Grayscale PDF first often reduces size while keeping readability.

If you only need part of the merged file, extract that subset with Extract pages (e.g., 1-3,7,10-12) instead of sharing the full document.

4) Fix issues without re-merging

5) Security (optional)

If you need a password, protect the final output using Protect PDF. Password protection is best as the last step because encrypted PDFs can be harder to process in other tools until you unlock them.

Privacy & retention

Files are stored temporarily for processing and deleted on scheduled cleanup (typically within 12 hours). If your document is highly sensitive, consider using offline tools on your own machine.

Troubleshooting

  • Upload fails: try a smaller file or compress first; for very large PDFs, split into parts with Split PDF.
  • Output looks blurry: avoid aggressive compression on scans; try Grayscale then Medium compression.
  • Encrypted PDF: unlock it first (requires password) using Unlock PDF.

How it works

  1. Upload at least 2 PDF files.
  2. Click Process to merge them into one PDF.
  3. Download and verify the result, then compress/protect if needed.

FAQ

Is it free?
Yes — this tool is free to use. Limits may apply based on server capacity.
How many PDFs can I merge?
You can merge multiple PDFs. Very large batches may hit upload limits; merge in smaller groups if needed.
Does merging change layout or quality?
No. Merging keeps original pages. Quality changes only if you compress afterwards.
How do I control the order?
Upload in the desired order. Renaming files (01-, 02-, 03-) helps avoid mistakes.
My merged PDF is huge. What should I do?
Run Compress PDF; for scans, Grayscale first then Compress.
Can I delete pages after merging?
Yes — use Remove pages on the merged output.
Can I reorder pages after merging?
Yes — use Rearrange pages to set the new order.
Can I merge password-protected PDFs?
Only if you unlock them first (requires the password).
How long are my files stored?
Files are stored temporarily for processing and deleted on scheduled cleanup (typically within 12 hours).
What should I include when reporting an issue?
Send the tool URL, file size, and exact error message via the Contact form.

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Privacy note: files are stored temporarily for processing and deleted on scheduled cleanup (typically within 12 hours).
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