Free Online Tool

Merge PDF Files Online

Combine multiple PDF files into a single document. Reorder pages, preview the result, and download instantly — 100% in your browser, no upload.

100% private
Reorder pages
Lossless merge

Merge PDF Tool

Runs in your browser

Drop your PDF files here

or browse files from your device

PDF only · Max 50 MB each
0 PDF files selected

Use the up/down arrows to reorder PDFs — the merged file follows this order.

Output Name

.pdf extension will be added automatically

Merge Info

Files: 0
Total pages: 0
Max: 20 files · 50 MB each

Merging PDFs…

Processing files…

Merge Complete

Files Merged 0
Total Pages 0
Ready to download

Why Merge PDFs?

Combining PDFs into one file has many practical benefits:

  • Simplify email attachments — one file instead of 5-10
  • Submit as a single document — job applications, legal filings, tax returns
  • Easier archiving — one file per project, not scattered parts
  • Better for printing — one print job, correct order guaranteed
  • Reduced clutter — organized documents in one PDF
  • Complete records — combine invoices, receipts, contracts into one file

Common use cases

ScenarioMerged PDF Contains
Job applicationCover letter + Resume + References
Tax filingForm + W-2s + Receipts
Legal filingComplaint + Exhibits + Proof of service
Client proposalExecutive summary + Scope + Pricing
Loan applicationApplication + ID + Pay stubs + Bank statements
ReportCover page + Content + Appendices

How to Merge PDFs in 3 Steps

  1. Upload your PDFs

    Drag and drop PDF files into the tool above, or click Choose PDF Files. Files up to 50 MB each, up to 20 PDFs per merge.

  2. Reorder the files

    Use the up and down arrows next to each file to arrange them in the exact order you want in the final PDF. The page count is shown so you know what to expect.

  3. Merge and download

    Click Merge PDFs. Preview the total page count, then click Download Merged PDF to save the combined document.

Key Features

Combine Multiple PDFs

Merge up to 20 PDF files into one document at once.

Reorder Freely

Arrange files with up/down arrows before merging.

Lossless Merge

Original pages are preserved exactly — text, images, formatting intact.

Page Count Preview

See total pages before merging — no surprises.

100% Private

All merging happens in your browser — files never leave your device.

Fast

Merge in seconds — no queue, no waiting.

Best Practices

Before merging

  • Preview the order — the merged PDF follows the file list exactly
  • Check page counts — if a file seems larger than expected, verify contents
  • Rename files if needed for clarity (they're stored temporarily)
  • Watch file sizes — merging many large PDFs can slow the browser

After merging

  • Verify page count — sum of individual files should match total
  • Check key pages — open the PDF and scan beginning, middle, end
  • Compress if needed — if the merged PDF is very large, consider compressing
  • Keep the originals — always retain original PDFs until you confirm the merged file

More PDF Tools

Frequently Asked Questions

Upload your PDF files, arrange them in the order you want using the up/down arrows, then click Merge PDFs. The tool combines them into a single document that you can download immediately.

Yes. Image Size Reducer's Merge PDF tool is completely free — no sign-up, no watermarks, no file limits.

You can merge up to 20 PDF files at once, each up to 50 MB. For larger batches, merge in multiple rounds.

Yes. After uploading, use the up and down arrows next to each file to reorder them. The final PDF will follow this order.

No. All PDF merging happens in your browser using the pdf-lib library. Your files never leave your device — complete privacy.

No. Merging is lossless — the original PDF pages are preserved exactly. Text, images, and formatting remain intact. This is different from image compression, where quality can degrade.

Not directly. If a PDF requires a password to open, you'll need to unlock it first (in Adobe Acrobat or another tool). Once unlocked, merge it here. Password-protected files will fail to load.