How many PDFs can I merge at once?

There is no hard limit. The tool merges as many PDFs as your browser's memory allows, typically dozens of multi-page documents on a modern device. All merging happens in your browser using pdf-lib.

Is my PDF uploaded to a server?

All merging is performed in your browser using pdf-lib, a JavaScript PDF library. Our servers are not involved at any point.

Can I reorder the PDFs before merging?

Yes. Use the drag handles to reorder files, or the arrow buttons on touch devices. The merged PDF follows the order shown in the list.

Are bookmarks and hyperlinks preserved?

Basic page content is preserved. Some complex PDF features like interactive forms, multimedia, and bookmarks may not carry over depending on the source files.

Merge PDF

Merge PDF is a PDF tool that combines multiple PDF files into a single document. It supports drag-and-drop reordering, previews each file's page count, and outputs a single merged PDF in one click. The tool runs in your browser.

Drop PDF files here or click to browse

You can add multiple files

Dedicated pages

Direct links for common merge scenarios.

Combine Two PDF Files

Merge exactly two PDF files into one. Drag and drop both files, reorder if needed, and download the combined PDF. All processing runs in your browser.

Merge Multiple PDF Files

Combine as many PDF files as you need into a single PDF. Add, reorder, remove, and merge. Entirely in your browser.

Merge PDF Files Online

Merge PDF files online for free. Add your PDFs, set the order, and download the result. No registration. Runs entirely in your browser.

Merge PDF Files Without Uploading

Merge PDF files without uploading anywhere. All processing runs locally in your browser using pdf-lib. No account required.

Merge PDF Files: No Account Required

Merge PDF files for free with no account, no sign-up, and no watermark. All processing runs in your browser. No registration required.

How to merge PDF files

Click "Add files" or drop your PDFs onto the upload area, add as many as you need.
Drag the rows to reorder the PDFs, or use the arrow buttons on mobile.
Click "Merge PDFs" and wait a moment while your browser combines the files.
Download the merged PDF directly.

Common uses

Combining multiple chapters or sections into a single document to share with others, use add page numbers after merging for easier navigation
Merging scanned pages into one file for archiving or submission
Combining multi-part reports or scanned receipts into a single organised PDF. Compress the merged file to reduce its size before emailing

Technical specification

Algorithm or formula: Sequential PDF concatenation using pdf-lib's copyPages followed by addPage to assemble a new PDFDocument with all source pages in the chosen order.
Browser API or library: pdf-lib for PDF read/write; pdfjs-dist for in-browser page-count preview. Standard File and Blob APIs for input and download.
Input limits: Each input PDF up to 100 MB. No hard limit on number of files; practical limit is browser memory.
Output: Single merged PDF (application/pdf) with concatenated pages, downloaded via Blob URL.
Known limitations: Interactive form fields, JavaScript actions, embedded multimedia, and document-level bookmarks are not preserved across merge. Page content, images, and text are retained.

Frequently asked questions

Is my PDF uploaded to a server?: No. All merging is performed locally in your browser using pdf-lib, a JavaScript PDF library.
Is there a limit on the number of PDFs I can merge?: There is no hard limit, you can add as many PDFs as your browser's memory allows. Very large collections may be slow on older devices.
Can I reorder the PDFs before merging?: Yes. Use the drag handles to reorder files, or the arrow buttons on touch devices. The merged PDF follows the order shown in the list.
Are bookmarks and hyperlinks preserved?: Basic page content is preserved. Some complex PDF features like interactive forms, multimedia, and bookmarks may not carry over depending on the source files.

Reviewed and tested May 26, 2026.