Organize PDF · guide
What Merge PDF does
Merge PDF combines two or more PDFs into one file, with the pages in the order the grid shows. Choose all the files together, then drag pages into any order with a mouse, across files as well as within them, and turn or remove pages before merging. On a touch screen, dragging scrolls the grid instead, so the pages keep the order the files arrive in. Every page is copied without being re-encoded, so text and images keep their quality and bookmarks carry across. The files are opened by your browser and never uploaded, so there is no size or file-count limit beyond your device's memory.
How to combine PDF files into one
- Add all your PDFs at once Select or drop every PDF you want to combine in one go, because choosing files again replaces the set. They open in this browser tab and are not uploaded.
- Arrange the pages With a mouse, drag pages into the order you want, across files as well as within them; a coloured strip on each page shows which file it came from. On a touch screen, dragging scrolls the grid instead of moving a page, so reorder on a computer. Hover a page to turn or remove it, or click it to see it full size.
- Merge and save Select Merge PDFs, check that the page count in the result is what you expect, then save the new PDF. Your original files are left as they were.
Worked example
Assemble a job application: cover letter, résumé, then portfolio.
- Starting point
- Start with a one-page cover letter, a two-page résumé and a four-page portfolio, each saved as a PDF.
- What to do
- Choose the three files. Review the visible page grid and put the cover first, the résumé next and the portfolio last before running Merge.
- Result
- Expect one seven-page PDF. Open the result and check pages 1, 2, 4 and 7 to confirm the document boundaries and final page.
If the result is not right
If an input is rejected, open it in a PDF viewer first. A JPG, PNG or WebP image renamed with a .pdf extension is still an image: change the extension back, then convert it with Images to PDF before merging.
Limits worth knowing
- Combining pages is not the same as combining interactive forms. Check links and bookmarks in the saved copy before submitting it.
- This workflow stops on interactive forms rather than risk losing their fields. Use Flatten first and check every visible answer in that saved copy, then open the flattened PDF here. Keep the editable original; protected or XFA forms may need a compatible form application first.
Questions and answers
Can I add another PDF after I have started arranging the pages?
Not to the arrangement you have built. Choosing or dropping files again replaces the whole set, and the page order you made goes with it. Select every PDF you need in the file picker in one go, or drop them together, and then arrange. If you have already merged and forgot one, merge the result with the missing file.
Which order do the files start in, and how do I tell their pages apart?
The grid starts with the files in the order your device hands them over, which is not always the order you clicked, so check it before merging. Each page has a coloured strip for its file: pages with the same colour came from the same file, and the six colours repeat after six files. Under each page, the first number is its place in the merged file and the bracketed number is its page number in its own file, so 3 (was 1) sits third in the merged file but is page 1 of its own file. Drag pages with a mouse, or focus a page and press [ or ] to move it one place; on a touch screen dragging scrolls the grid, so reorder on a computer.
Can I merge JPG or PNG images in with my PDFs without losing quality?
Not directly: Merge PDF takes PDFs only and skips anything else, saying how many files it left out. Turn the images into a PDF first with JPG to PDF, which places a JPG in the page byte for byte and keeps PNG pixels unchanged; only WebP is re-encoded, as JPEG. Then merge that PDF with the others. Merging itself never recompresses anything.
Will merging change the quality or size of my pages?
No. Each page is copied as it is, without being re-rendered or recompressed, and keeps its own size and orientation, so an A4 file and a Letter file merged together stay A4 and Letter. Bookmarks are rebuilt to point at the right pages, and the title and author come from the file that supplies the first page. Accessibility tags, page labels, files attached to the document and hidden-layer settings in the source files are not carried into the merged file, so a layer that was switched off can show again, and links that jump from one page to another no longer go where they did.
Why does it refuse a fillable form or a digitally signed PDF?
Form fields belong to the document as a whole rather than to its pages, so copying the pages into a new file would leave the fields broken, and Merge PDF stops instead. Run the form through Flatten PDF, check the answers in the flattened copy, then merge that. A certificate-signed PDF keeps its signature in a form field and is refused for the same reason; a new file built from its pages could not keep that signature valid anyway, so send it alongside the merged file.
Is there a limit on how many PDFs I can merge, or how big they can be?
There is no file-count or file-size cap, because nothing is uploaded; the limit is your device's memory, so a stack of large scans merges more comfortably on a laptop than on an older phone. In a very long set, pages after the first 600 show a number instead of a picture but can still be moved. Any encrypted PDF is refused, including one that opens without a password but blocks printing or copying. Unlock PDF removes the encryption if you have the file's password; for a file that opens freely, that means its permissions (owner) password.