Job applications, tax packs, contracts with exhibits, class notes: they all end up as a pile of separate PDFs that someone wants as one file. Merging takes a minute. A few small decisions before you click decide whether the result looks professional.

Before you merge

Decide the order. Write it down if there are more than a few files: cover letter, main document, appendices. Renaming files with a number prefix (01, 02, 03) also keeps them in order on your computer.

Check orientation. A landscape spreadsheet printout in the middle of portrait pages is fine, but a sideways scan isn't. Fix those first with Rotate PDF.

Remove what you don't need. Blank pages and duplicate cover sheets make a merged file look careless. Delete Pages removes them before you combine.

How to merge

1. Open Merge PDF.
2. Add your files (each up to 50 MB).
3. Drag them into the final order.
4. Merge and download the combined PDF.

Scroll through the result once. It takes thirty seconds and catches a missing file or a misplaced section before someone else does.

After you merge

• Reorder any pages that ended up in the wrong place with Reorder Pages.
• Add page numbers so the whole document reads as one piece. Add Page Numbers numbers every page continuously, which matters for long submissions that refer to "page 14".
• Compress it if the total is large. Merged files add up quickly, and email limits are unforgiving. See how to compress a PDF for email.

Mixed page sizes

If one file is A4 and another is US Letter, the merged document keeps each page at its own size. That is acceptable on screen but can look uneven when printed. To make them uniform, run the combined file through Resize PDF.

When you need only part of a file

Merging whole files is not always what you want. To pull specific pages out of one document before combining, use Extract Pages, and to cut a large file into sections, see how to split PDF pages.

If the merge doesn't work

• A file is rejected: it may be password protected or damaged. Try Unlock PDF or Repair PDF on that file.
• You have more than 10 files: merge them in groups, then merge the groups.
• A file is over 50 MB: compress it first with Compress PDF.
• The order is wrong: fix it with Reorder Pages rather than merging again.

Frequently Asked Questions

Is there a limit to how many PDFs I can merge?

The standard merge tool accepts up to 10 files at a time. For larger sets, merge in groups and then merge the groups.

Will merging reduce quality?

No. Merging joins the pages without re-rendering them, so text and images stay as they were.

Can I merge password-protected PDFs?

Remove the password first with Unlock PDF if you have the right to do so, then merge.

Does the merged file keep bookmarks and links?

Simple links inside a page usually survive. Bookmarks from the original files may not, so check them if you rely on them.