Merge PDFs,
into one file.

Combine multiple PDF files into a single document in seconds. Free, fast, no install β€” right in your browser.

⚑ Instant πŸ”’ Private πŸ†“ Free πŸ“¦ No install
Drop PDF files here
or click to browse (select more than one)
Files never leave your device β€” merging happens locally in your browser.
Files mergedβ€”
Pages totalβ€”
Combined sizeβ€”
↓ Download merged PDF

How to merge PDF files online β€” in 3 steps

SlimIO's PDF merger joins two or more PDF documents into a single file. Everything runs in your browser, so your documents stay private and there is nothing to install.

Why merge PDFs?

Whether you are combining scanned pages, joining a report with its appendices, or assembling a bundle for a submission, a single PDF is easier to share, email, and print. No account, no watermark, no waiting in a queue.

Is it a free PDF merger?

Yes. Merging is free, with no signup and no watermark, up to 20 operations a day. You can also compress a PDF before or after merging to keep the final file small.

PDF merger β€” FAQ

How do I merge PDF files for free?

Open SlimIO's PDF merger, drop in two or more PDF files, reorder them if you like, and click Merge. The result downloads as a single combined PDF. It runs in your browser, so there is nothing to install and no account needed.

Is it safe to merge PDFs online?

Yes. SlimIO merges files locally in your browser, so your PDFs never leave your device and are not uploaded to any server.

How many PDF files can I merge at once?

You can merge as many PDF files as your browser memory allows. For very large batches, split the work into a few passes.

Can I change the order of the pages?

Yes. After selecting your files, use the move up/down buttons to reorder them before merging.

Does the free PDF merger have a limit?

The free tier includes a per-day operation limit. No signup is required, and you can start merging right away.

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