Merge PDF
Combine multiple PDFs into one unified document.
About Merge PDF
How to Merge PDF Files
Add at least two PDFs, put them in the order you need, choose Sequential, Interleave, or Duplex Scan Fix, then merge and download the result. The web and desktop tools do not impose a file-size ceiling; the practical limit is the memory available to your device and browser.
OxygenPDF reads the source files and creates the combined PDF on your device. Before merging, you can sort files by name, size, or page count, preview their pages, remove files, and rotate a complete source document.
Common Reasons to Merge PDFs
People merge PDFs for all kinds of reasons, but the problem is always the same: too many files, not enough patience to send them one by one.
Financial Paperwork
Combine invoices, receipts, and bank statements into a single file for expense reports, tax prep, or auditor requests.
Legal Documents
Courts and compliance teams want one document, not five loose files. Merge contracts with their amendments and signature pages.
Academic Submissions
University applications and journal submissions usually need everything in one PDF. Merge transcripts, letters, and your personal statement.
Business Reports
Pull together charts, narratives, and appendices from different departments into a single quarterly or board report.
Sequential, Interleave, and Duplex Scan Modes
Sequential mode appends each complete file in the order shown. Interleave takes page 1 from every source, then page 2 from every source, continuing until every page has been copied. Files do not need the same page count.
Duplex Scan Fix is for fronts and backs captured separately with a single-sided scanner. It reverses every second source file before interleaving the pages. Blank-page insertion is available in Sequential mode when each source document must begin on a fresh sheet.
Choose the Right Merge Mode
Pick the mode from the way the source documents should read, not from the number of files.
| Feature | Page order | Best for |
|---|---|---|
| Sequential | All of A, then all of B | Reports, contracts, and appendices |
| Interleave | A1, B1, A2, B2 | Questions and answers or parallel documents |
| Duplex Scan Fix | Alternate files; reverse every second source | Fronts and backs scanned separately |
What Stays on Your Device
OxygenPDF reads the source files and creates the merged PDF on your device. The PDF contents and passwords are not uploaded to OxygenPDF servers.
Local processing reduces the need to disclose document contents to a separate file-processing server. It does not, by itself, establish compliance with GDPR, HIPAA, an NDA, or an organization’s internal handling rules. Check the requirements that apply to your documents.
Limits and Important Behavior
Add at least two PDFs. The web and desktop tools accept files larger than 1GB and do not impose a fixed size ceiling; available device memory is the practical limit. The iPhone app refuses files above 50MB to prevent iOS from terminating the process. The original files are not modified.
A protected PDF requires its correct password. Unlocking a protected source rasterizes its pages, so they remain visible but lose searchable and selectable text. Merging also creates a new document, so inspect bookmarks, form behavior, annotations, links, and digital signatures before treating the result as final.
Merge PDF: Frequently Asked Questions
Common questions about this tool and how it works.
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Continue working with your PDFs
Compress PDF
Compress PDFs locally without uploading. Pick a preset or set a target file size.
Protect PDF
Encrypt your PDF with a password.
Rotate PDF
Rotate pages clockwise or counter-clockwise.
Split PDF
Separate one PDF into individual pages or files.
Edit PDF
Add text, images, drawings, shapes, and highlights to your PDF.
Sign PDF
Add electronic signatures to your PDF documents.