How to merge PDF files
- Drop your PDF files onto the box above, or click it to pick them from your computer. You can add as many as you like.
- Check the order in the list. Files are merged top to bottom, in the order you added them — remove any you added by mistake with the ✕ button.
- Press Merge into one PDF. The work runs on your own device, so a large merge is limited only by your computer, not by an upload.
- The merged PDF appears below with a Save button. Nothing was sent anywhere — the counter beside it still reads zero bytes uploaded.
About this tool
Merging PDF files is the most common thing people need a PDF tool for: combining a signed contract with its annexes, stapling scanned receipts into one expense claim, or joining chapters into a single report before printing. This free PDF merger combines any number of documents into one file without uploading them.
That last part is the difference. Most online PDF merge tools send your document to a server, process it there, and hand back a link. For a bank statement or a signed agreement, that means handing a copy of a private document to a company you know nothing about. SiriTools merges the files inside your browser tab using JavaScript, so the document never leaves your machine — and because we are not paying for server time, there is no file-size limit and no cap on how many times a day you use it.
Page order, page size and orientation are preserved exactly as they were in the source files. Mixed page sizes are kept as-is rather than being forced onto one paper size.
Frequently asked questions
- Is this PDF merger really free?
- Yes, with no account, no watermark and no daily limit. The site is supported by advertising rather than by charging for the tools.
- Are my PDF files uploaded to a server?
- No. The merge runs entirely in your browser. You can confirm it: open your browser’s developer tools, switch to the Network tab, and merge a file — no request carries your document. The counter at the top of this page shows file bytes uploaded, and it stays at zero.
- Is there a file size limit?
- There is no limit imposed by us. The practical ceiling is your device’s available memory, since the whole document is held in the browser while it works.
- Can I change the order of the files?
- Not by dragging, no. Files merge in the order you add them, so to reorder one, remove it with the ✕ button and add it again in the position you want.
- Does merging reduce quality?
- No. Pages are copied across intact — text stays as text and images are not re-encoded. If you also need a smaller file afterwards, use Compress PDF.