How to merge PDF files
- Drop your PDFs Drag them all in at once, or click to browse for them. Every page turns into a thumbnail right away.
- Arrange the pages. Drag them into any order. Pages from different files can interleave, and you can rotate or discard any of them.
- Click Merge, then Download. The combined PDF is assembled on the spot and saved to your downloads folder.
Merging without uploading
Most online PDF mergers want your documents on their servers first. You wait for the upload, you wait for the download, and in between your contracts sit on a stranger's computer (here's what that involves). Sleek PDF uses your browser's own processing power instead. On a big stack of scans that's faster, and it's the only way to merge documents you aren't allowed to send anywhere. Works with the wifi off, too.
What merging actually does to your files
Pages are copied into the new document exactly as they are. Nothing is re-rendered or recompressed: the text stays selectable, the images keep every pixel, and each page carries its fonts. The trade-off is size. A merged file weighs roughly what its parts weighed together, so combining three 4 MB scans produces a 12 MB document. If the result then has to fit under an attachment cap, compress it as a second step; the order matters, because one compression pass costs less quality than three.
Getting the order right before you commit
The usual reason to merge is that somebody asked for one file: an application wants cover letter, CV and certificates as a single upload, a landlord wants three months of payslips, an expense claim needs every receipt behind the form. The thumbnails are there so you can assemble that packet exactly as asked. Files land in the order you add them, but nothing is fixed: drag any page anywhere, including in between the pages of a different file, rotate the sideways scans, and drop any blank backsides left over from scanning.
Two neighbouring jobs have their own tools. If the pages you need are buried inside one large document, pull them out first and merge the extract. And when the job is bigger than stacking files end to end, with lots of rearranging across many documents and several outputs, the organize workspace is the same idea with more room to work.
Common uses for merging PDFs
- Combine book or report chapters: one manuscript out of a folder full of chapter files.
- Merge receipts and invoices: a month of receipts becomes a single expense claim.
- Assemble an application packet: CV, cover letter and certificates joined into the one file the portal will accept.
- Join scanned pages: your scanner saved every page separately again. Put them back together.
Frequently asked questions
Is it really free, with no limits?
No daily caps, no watermarks, no ceiling on how many files you throw in, no premium tier. Your machine does the work, so it costs us nothing when you use it.
Are my PDFs uploaded anywhere?
They aren't. Your browser opens the files straight off your disk and builds the result there. If you'd rather have proof than a promise, open the Network tab in your developer tools and merge something. Nothing goes out.
Can I reorder or delete pages before merging?
That's the point of the thumbnails. Drag pages into any order, rotate them, throw out the ones you don't need. Keyboard works too: focus a page, press Space, then use the arrow keys.
Is there a file size limit?
None that we impose. The real ceiling is your device's memory. Past roughly 150MB you'll get a soft warning, and merging in two batches usually gets you there.
Does it work offline?
After the first visit, yes. No server is involved, so once the page is cached it works on a plane.