Frequently Asked Questions
Everything you need to know about merging PDF files online
It's simple! Just drag and drop your PDF files into the upload area, arrange them in your desired order by dragging, then click the 'Merge PDFs' button. Your merged document will be ready for download in seconds.
Yes, absolutely! All PDF processing happens directly in your browser using client-side JavaScript. Your files never leave your device and are not uploaded to our servers. This ensures complete privacy and security of your documents.
You can upload PDF files up to 100MB each. For larger files, we recommend compressing them first or splitting them into smaller parts before merging.
You can merge up to 50 PDF files in a single operation. This should be sufficient for most use cases, from combining a few documents to merging entire document collections.
Our PDF Ninja works in all modern browsers including Chrome, Firefox, Safari, Edge, and Opera. We recommend using the latest version of your browser for the best experience.
No registration required! You can use our PDF Ninja tool immediately without creating an account, providing personal information, or signing up for anything.
Yes, our PDF Ninja is completely free to use. There are no hidden fees, subscription requirements, or usage limits. You can merge as many PDFs as you need without any cost.
Currently, we support PDF files only. The merged output will also be in PDF format. We're working on adding support for other document formats in the future.
No, PDF Ninja preserves the original quality of your documents. We don't compress or re-encode the content. The merged PDF will contain all pages in their original quality with fonts, images, and formatting intact.
Yes! You can easily reorder your uploaded PDFs by dragging and dropping them into the desired position before clicking the merge button. This gives you complete control over the final document structure.
Absolutely! PDF Ninja is fully responsive and works on all devices including smartphones and tablets. You can merge or split PDFs on the go using your mobile browser.
Currently, PDF Ninja cannot process password-protected or encrypted PDF files. You'll need to remove the password protection before merging. We're working on adding support for password-protected files in the future.
Use our Split PDF tool! Upload your PDF, choose a split mode (all pages, by range, extract specific, or fixed size), select your preferences, and download the individual files. It takes just 20-40 seconds.
PDF Ninja offers 4 split modes: (1) All Pages - splits every page into a separate file, (2) By Range - splits according to specified page ranges like 1-3, 5-7, (3) Extract - pulls out specific selected pages, and (4) Fixed Size - divides into equal chunks of N pages each.
PDF Ninja is completely free with reasonable limits: maximum 50 files per merge, 100MB per file, and up to 100-page documents for splitting. These limits accommodate 99% of typical use cases without any restrictions.
Your files are not stored at all! Since all processing happens in your browser, we never receive or store your files on our servers. Once you close the browser tab, everything is gone. This ensures maximum privacy.
You need an internet connection initially to load the PDF Ninja web app. However, once loaded, the actual PDF processing happens offline in your browser without requiring further internet connectivity.
Processing speed depends on file sizes and quantity. Typically: merging 2-10 PDFs takes 10-30 seconds, merging 50 PDFs takes 1-2 minutes, and splitting a 100-page PDF takes 30-40 seconds. All processing happens instantly in your browser.
When merging PDFs, the metadata from the first document is preserved. Bookmarks are currently not merged but we're working on adding this feature. When splitting, each resulting PDF maintains its original metadata.
Errors typically occur with corrupted PDFs, unsupported features, or very large files. Try: (1) ensuring your PDF isn't corrupted, (2) reducing file size, (3) using a different browser, or (4) splitting large merges into smaller batches.
PDF Ninja is completely free, requires no installation or registration, processes files in your browser for maximum security, and works on any device. Other services often charge $5-25/month, require software installation or account creation, and upload files to their servers.
Yes! PDF Ninja is free for both personal and commercial use. You can use it for business documents, client contracts, invoices, presentations, or any professional work without any licensing fees or restrictions.
We're actively developing additional tools including: rotate PDF pages, compress PDF files, convert PDF to images, add watermarks, protect PDFs with passwords, and more. Check back regularly for new features!