Why merging is usually the last step, not the first
Merging is rarely something you set out to do. It shows up at the end of something else: the scanner produced one file per page, the bank sent three statements as three attachments, the contract came back signed but only page four. What the other side actually wants is one file, in one order, that opens once.
This tool does that and nothing else. Add the files, drag them into the order you want, merge, download. Page content is copied across untouched — text stays selectable, links stay clickable, and nothing is re-rendered into an image along the way.
How to use it
Drop two or more PDFs onto the page, or browse for them. Each file appears as a row with its page count, so you can sanity-check that the 40-page report really is the 40-page report before you commit.
Drag the rows to set the order. The merged document follows the list top to bottom. Click merge and the combined file downloads immediately.
Where it earns its keep
Expense claims, where receipts arrive as a dozen separate scans and the finance system accepts one attachment. Job applications that ask for CV, cover letter and certificates as a single PDF. Court and government filings with a strict one-document rule. Scanners that split a double-sided stack into odd and even files.
It is also the fix for the most common email problem there is: five attachments that should have been one, sent to someone who will open exactly the first.
Three things worth checking before you merge
Page size. A bundle mixing A4 and Letter, or portrait and landscape, prints badly and looks careless. It is worth opening the odd file out and deciding whether to live with it or re-export it at a consistent size before combining.
Order of scanned batches. A scanner that produced one file per page usually names them in a sortable order, but not always — some name by timestamp, which breaks as soon as a page is rescanned. Check the first and last row before merging rather than after.
Size. Merging does not compress. Five 4 MB scans become one 20 MB file, which is exactly the size most email systems refuse. If the merged file is destined for an attachment, compress it afterwards rather than wondering why it bounced.
What happens to your files
Every one of these runs in your browser. The file is read from your disk, processed in memory and handed back as a download — there is no upload, no server copy and no account.
That matters more than it sounds for merging in particular, because the things people merge — statements, contracts, medical letters, ID scans — tend to be the documents they would least like to hand to a stranger's server.
Frequently asked questions
Is there a limit on how many files I can merge? The practical limit is your device's memory rather than a rule we impose. Dozens of ordinary documents are fine; hundreds of scan-heavy files may be slow on an older phone. In practice the ceiling you hit first is patience rather than capacity — a browser tab churning through 200 scanned pages is doing real work on your CPU.
Does merging reduce quality? No. Pages are copied across as they are. Nothing is re-compressed or rasterised, so text stays text. That also means a merged bundle is the sum of its parts in file size, so five 4 MB scans give you a 20 MB document.
Can I change the order after adding files? Yes. Drag the rows into any order before you merge — the output follows the list exactly. There is no separate save step for the order: whatever the list shows when you press merge is what you get.
Are my files uploaded? No. Everything happens in your browser and the merged file is generated locally as a download. The merged file is assembled in memory and handed to your browser's download mechanism, which is why it appears instantly rather than after an upload round trip.
Related: Split PDF · Organize Pages · Compress PDF · All tools