Merging PDFs is simple: 1) Upload your PDF files by dragging them into the drop zone or clicking "Select Files", 2) Arrange them in your preferred order using the move up/down buttons, 3) Choose your merge options, 4) Click "Merge PDFs", and 5) Download your combined file. The entire process happens in your browser for maximum privacy.

Our tool is designed specifically for PDF files. While some online tools support merging other file types (like images or Office documents), we focus exclusively on PDFs to ensure the highest quality results. All uploaded files must have the .pdf extension.

Our browser-based tool can handle up to 20 PDF files at once, with each file up to 50MB. The total combined size shouldn't exceed 100MB for optimal performance. For larger projects, we recommend using our desktop application which has higher limits.

Absolutely. Our tool processes all files directly in your browser - your PDFs are never uploaded to any server. This means your documents never leave your computer, ensuring complete privacy. You can verify this by using your browser's network monitor during the merge process.

Since all processing happens in your browser, your files are only stored in your computer's temporary memory during the merge process. Once you close the browser tab or refresh the page, all file data is completely cleared. We don't store, track, or analyze any of your documents.

Our browser-based tool cannot process password-protected PDFs due to security limitations. For merging encrypted files, you would need to remove the password protection first using the original password, then merge the files. Our desktop application has additional capabilities for handling protected documents.

Our current browser version merges all pages from each PDF in sequence. For selective page merging, you would need to: 1) Split your PDFs into separate files containing only the pages you want, 2) Merge those files together. Our desktop application includes a page selection feature for more control over the merging process.

Yes, our merger preserves existing bookmarks and hyperlinks within the original PDFs. However, complex interactive elements like form fields or multimedia content may not always transfer perfectly. For documents with advanced features, we recommend testing with a few pages first before merging large files.

The browser version focuses on basic merging without additional modifications. For adding page numbers, watermarks, or other enhancements, you would need to: 1) Merge your files first, 2) Use a separate PDF editing tool to add those elements. Our desktop application includes these advanced features in the premium version.

PDF file size depends on many factors: 1) High-resolution images, 2) Embedded fonts, 3) Multiple versions of the same content. The merger preserves all original content, which can increase size. For smaller files, optimize your source PDFs before merging or use compression tools afterward.

Some PDFs may cause issues due to: 1) Complex encryption, 2) Corrupted structure, 3) Unsupported features. Try: 1) Opening and re-saving the PDF in another application, 2) Converting to a new PDF using a virtual printer, 3) Breaking the file into smaller parts for merging separately.

Page order issues typically occur when: 1) Files have different page orientations (portrait/landscape), 2) Some PDFs have cover pages affecting numbering, 3) The "Alphabetical" sort option was used unintentionally. Double-check your file order before merging and consider standardizing page sizes first.