--- title: "How to merge PDF files into one | ToolSugar" description: "Combine several PDFs into a single file in the right page order, and find out what to do with locked files and very large batches." canonical: https://toolsugar.com/blog/how-to-merge-pdf-files image: https://toolsugar.com/og.png --- # How to merge PDF files into one document Updated 2026-11-09 To merge PDF files, add them to a list, put the list in the order you want the pages to appear, and save the result as one file. Merge PDF does this inside your browser. Your files stay on your device, the pages are copied as they are, and you download a single merged.pdf at the end. [Open Merge PDF](https://toolsugar.com/tools/merge-pdf) ## Merge PDFs in four steps You need two or more PDF files. They can come from different programs, and they can have different page sizes. 1. Choose the PDFs, or drop them on the box. Adding more later keeps the files already listed. 2. Use the up and down arrows on each row to set the order. The cross removes a file. 3. Press Merge PDFs and wait for the page count to appear. 4. Download merged.pdf. ## How the page order is decided The result follows the list from top to bottom. The first file contributes all its pages, then the second, and so on. Inside each file the pages keep the order they already had. If one file needs to appear in the middle of another, you cannot interleave single pages here. Split the outer file first with Split PDF, then merge the pieces and the middle file in the order you need. ## Will the merged file look the same? Yes. The pages are copied into the new document without being drawn again, so text stays sharp and you can still select and search it. Mixed page sizes also stay as they were, so an A4 page next to a letter page is fine. The size of the result is close to the sum of the inputs. If it is too big to send, run it through Compress PDF afterwards. ## Combining a locked PDF A PDF protected with a password cannot be read by the tool. It stops and names the file that is locked, so you know which one to fix. Open that file in the program that made it, remove the password, save a copy, and add the copy to the list. Scans and photos work as long as they are already PDFs. For loose pictures, turn them into a PDF with Image to PDF first. ## When a large batch fails There is no file count limit in the tool. Your browser has to hold every file in memory while it builds the result, so a long list of big scans can run out of room on a phone. Merge in two rounds instead, then merge the two results. ## Questions ### How do I add a PDF I forgot? Choose or drop more files at any point before you press Merge PDFs. They are added to the bottom of the list, and you can move them with the arrows. ### Can I merge PDFs on my phone? Yes, in a mobile browser. Keep the batch small, because the files are held in memory while the new document is built. ### Does the merge keep my text searchable? Yes. Nothing is turned into a picture, so any text that was selectable in the originals is selectable in merged.pdf. ### Why is my merged file so large? It holds every page of every input, so it is about as big as all of them together. Compress it afterwards if you need a smaller file. [Open Merge PDF](https://toolsugar.com/tools/merge-pdf) ## Related guides - [How to split a PDF into separate files](https://toolsugar.com/blog/how-to-split-a-pdf) - [How to compress a PDF to a smaller size](https://toolsugar.com/blog/how-to-compress-a-pdf) - [How to convert images to a PDF](https://toolsugar.com/blog/how-to-convert-images-to-pdf) - [How to rotate pages in a PDF](https://toolsugar.com/blog/how-to-rotate-a-pdf) ## Comparisons - [iLovePDF alternative](https://toolsugar.com/alternatives/ilovepdf-alternative) - [Smallpdf alternative](https://toolsugar.com/alternatives/smallpdf-alternative)