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Merge PDF

Merge PDF files online for free. Combine multiple PDF documents, reports, and scanned pages into one clean, organized file. Reorder documents with intuitive controls, view instant page counts, and download merged PDFs with 100% in-browser privacy and zero file size limits.

Drop PDF files here, or click to browse

Select two or more PDF documents to combine into a single clean file. Reorder, set page ranges, and merge in your browser.

Step-by-Step Instructions

Upload Multiple PDF Documents

Select or drag and drop two or more PDF files into the merging workspace.

Reorder and Organize Pages

Drag and drop file thumbnails to arrange the exact document order or delete unwanted pages before combining.

Execute Instant Page Merge

The engine stitches page trees, cross-reference tables, and font dictionaries into a single cohesive master PDF.

Download Merged Master PDF

Download your unified, perfectly organized multi-page PDF document in seconds.

Key Features & Capabilities

Combines unlimited PDF documents into a single organized master file
Interactive visual thumbnail preview with intuitive drag-and-drop file reordering
Preserves original document formatting, vector fonts, high-res images, hyperlinks, and page orientations
Automatic cross-reference table (`xref`) and page catalog reconstruction
Fast client-side PDF concatenation executing in milliseconds via `pdf-lib`
100% private in-browser merging: confidential contracts and reports never leave your device

Frequently Asked Questions

How does the PDF merger combine multiple files into one?

The tool utilizes client-side PDF document manipulation (`pdf-lib`). It copies the visual page objects, content streams, and resource dictionaries from each source PDF and binds them into a newly structured document catalog with a unified page tree and cross-reference table.

Can I combine PDFs with different page sizes (e.g., A4 and US Letter)?

Yes. The merger respects the individual MediaBox dimensions of each page, allowing you to combine documents with mixed page sizes (A4, Letter, Legal, Tabloid) and mixed portrait/landscape orientations without distortion.

Will form fields, hyperlinks, and bookmarks be preserved after merging?

Standard page annotations, internal hyperlinks, and vector artwork are preserved in the merged document.

Is there any file count or size limit for merging PDFs?

No. Because merging runs locally in your browser using your computer's RAM, you can combine dozens of documents without server timeouts or file limits.