Merge multiple PDF files into one document in the order you upload them.
Page-preserving processing runs locally. This workspace supports up to 50 PDFs, 200 total source/output pages and 200 MiB per batch. Encrypted PDFs and interactive form/signature fields are rejected; the original is never flattened automatically. Check internal links and bookmarks in the output.
Drag & drop files here
or use the button below · processed locally on your device
Free file tool
Free PDF Merger online
Merge multiple PDF files into one document in the order you upload them. Use the tool directly in your browser with no sign-up. It supports multiple source files in the same session, so it also works as a free batch tool when you have more than one file.
Free to use
No payment required for this tool.
Batch conversion
Queue multiple source files in one session.
Browser-based
The conversion workflow runs from the web page on your device.
No sign-up
Start the file workflow without creating an account.
What PDF Merger is useful for
✓Organising pages before submission or sharing
✓Creating a clean working copy of a PDF
✓Keeping only the pages and order you actually need
Input and output checks
Accepted input: pdf.
✓Open the downloaded output before deleting or replacing the source file.
✓Check the details that matter for your use: page count, dimensions, orientation, text, duration or metadata.
✓For batch jobs, confirm every queued file produced the expected output.
How to use this calculator: PDF Merger
1Choose your PDF files. Merger needs at least two; the page workspace validates every source before processing.
2Review the numbered page grid. Source file and source page remain visible beneath every preview.
3Select by page number, drag or use arrows to reorder, and review changes in the grid. Use the operation controls before saving.
4Review the output plan, run the operation and check the verified page count and source-to-output mapping.
5Preview and download the generated PDF(s). Keep the originals and review links and document-level features.
Worked conversion example
Example: add a 2-page cover PDF, a 10-page report and a 1-page appendix in that order. The output is one 13-page PDF; queue order becomes page order.
Accepted input
pdf
Batch behaviour
Multiple files supported
How the browser process works
Merge multiple PDF files into one document in the order you upload them. The page sends the selected file and settings to its pdf-merge browser engine, creates a new output and downloads it without overwriting the source.
Page-preserving processing runs locally. This workspace supports up to 50 PDFs, 200 total source/output pages and 200 MiB per batch. Encrypted PDFs and interactive form/signature fields are rejected; the original is never flattened automatically. Check internal links and bookmarks in the output.
Privacy, quality checks and limitations
Keep the original file until the downloaded output has been opened and checked.
Verify page count, orientation, dimensions, text legibility, audio/video duration and metadata relevant to your use.
Browser-local processing reduces routine upload exposure, but your device, browser extensions and download location still matter.
A converted preview is not proof of legal authenticity, archival compliance, accessibility or digital-signature validity.
Use this tool for a real document task
Build one solar-project submission from the cover letter, module datasheet and site drawings. Add PDFs in document order, then inspect individual pages before combining.
A result you can check
A 2-page covering letter plus a 3-page drawing set should produce 5 pages. Move the cover page first and use the source labels to distinguish files with the same printed page numbers.
Merging copies page content; it is not PDF compression. Mixed A4/A3 page sizes remain mixed. Bookmarks and links to pages in another source document need checking in the combined result.
The browser copies original PDF page content without rasterising it. It rejects encrypted PDFs and interactive form/signature fields rather than flattening them or producing a misleading replacement. Work on a page-only copy when appropriate; retain the interactive/signed original. Files are not uploaded. Maximum: 50 files, 200 total source/output pages, 200 MiB per job.
Merge multiple PDF files into one document online. PDF merging is useful when separate reports, scanned pages, forms, or attachments need to be combined into a single file.
Why merge PDF files?
Combine multiple reports into one document.
Join scanned pages from separate files.
Create one submission file from several PDFs.
Reduce the number of files that need to be shared.
PDF merge order
The current merge workflow combines the selected PDF files in their upload/selection order. Check the final document before sharing it.
Related PDF Tools
Continue with a related PDF task using another OneCalcApp tool.
